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Zengin K, Inan C, Nalcacioglu R, Demirbag Z. The Function of TER94 of Spodoptera frugiperda 9 Cells When Infected With Invertebrate Iridescent Virus-6. J Basic Microbiol 2025:e70045. [PMID: 40357853 DOI: 10.1002/jobm.70045] [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: 02/18/2025] [Revised: 04/15/2025] [Accepted: 04/30/2025] [Indexed: 05/15/2025]
Abstract
The 118 L protein in the envelope of the Invertebrate iridescent virus 6 (IIV6) is responsible for binding to receptors on the surface of permissive cells. We previously elucidated its function by silencing its gene and neutralizing the protein with antibodies. In this study, we aimed to identify the cellular protein that interacts with 118 L protein during virus infection. Membrane proteins from Spodoptera frugiperda 9 (Sf9) cells were separated by SDS-PAGE and electro-transferred to a nitrocellulose membrane. Using a virus overlay protein binding assay (VOPBA), the 118 L protein purified by His-tag was shown to interact with a cellular protein larger than 100 kDa. Analysis of the cellular protein by LC-MS/MS revealed that the transitional endoplasmic reticulum ATPase (TER94) was the highest-scoring protein. Docking analysis using the HADDOCK2.4 program confirmed the interaction of 118 L with TER94. Furthermore, a pull-down experiment was performed between the TER94 produced by His-tag in the baculovirus expression system, and the 118 L protein produced by GST-tag in the bacterial expression system. The interaction between these two proteins was visualized by western blot analysis using a monoclonal anti-GST antibody. These results indicate that TER94 is a binding protein for 118 L and plays a significant role in the entry of IIV6 into Sf9 cells.
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Affiliation(s)
- Kubra Zengin
- Faculty of Sciences, Department of Biology, Karadeniz Technical University, Trabzon, Türkiye
| | - Cihan Inan
- Faculty of Sciences, Department of Molecular Biology and Genetics, Karadeniz Technical University, Trabzon, Türkiye
| | - Remziye Nalcacioglu
- Faculty of Sciences, Department of Biology, Karadeniz Technical University, Trabzon, Türkiye
| | - Zihni Demirbag
- Faculty of Sciences, Department of Biology, Karadeniz Technical University, Trabzon, Türkiye
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Altun B, Zengin K, Yayli Dabag S, Yesilyurt A, Nalcacioglu R, Demirbag Z. Characterization of an envelope protein 118L in invertebrate iridescent virus 6 (IIV6). Virus Genes 2024; 60:549-558. [PMID: 38922563 DOI: 10.1007/s11262-024-02082-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2024] [Accepted: 05/30/2024] [Indexed: 06/27/2024]
Abstract
Invertebrate iridescent virus 6 (IIV6) is a nucleocytoplasmic insect virus and a member of the family Iridoviridae. The IIV6 genome consists of 212,482 bp of linear dsDNA with 215 non-overlapping and putative protein-encoding ORFs. The IIV6 118L ORF is conserved in all sequenced members of the Iridoviridae and encodes a 515 amino acid protein with three predicted transmembrane domains and several N-glycosylation/N-myristoylation sites. In this study, we characterized the 118L ORF by both deleting it from the viral genome and silencing its expression with dsRNA in infected insect cells. The homologous recombination method was used to replace 118L ORF with the green fluorescent protein (gfp) gene. Virus mutants in which the 118L gene sequence had been replaced with gfp were identified by fluorescence microscopy but could not be propagated separately from the wild-type virus in insect cells. Unsuccessful attempts to isolate the mutant virus with the 118L gene deletion suggested that the protein is essential for virus replication. To support this result, we used dsRNA to target the 118L gene and showed that treatment resulted in a 99% reduction in virus titer. Subsequently, we demonstrated that 118L-specific antibodies produced against the 118L protein expressed in the baculovirus vector system were able to neutralize the virus infection. All these results indicate that 118L is a viral envelope protein that is required for the initiation of virus replication.
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Affiliation(s)
- Betul Altun
- Department of Molecular Biology and Genetic, Faculty of Sciences, Karadeniz Technical University, 61080, Trabzon, Turkey
| | - Kubra Zengin
- Department of Biology, Faculty of Sciences, Karadeniz Technical University, 61080, Trabzon, Turkey
| | - Sevde Yayli Dabag
- Department of Biology, Faculty of Sciences, Karadeniz Technical University, 61080, Trabzon, Turkey
| | - Aydin Yesilyurt
- Tonya Vocational School, Trabzon University, Trabzon, Turkey
| | - Remziye Nalcacioglu
- Department of Biology, Faculty of Sciences, Karadeniz Technical University, 61080, Trabzon, Turkey
| | - Zihni Demirbag
- Department of Biology, Faculty of Sciences, Karadeniz Technical University, 61080, Trabzon, Turkey.
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SiouNing AS, Seong TS, Kondo H, Bhassu S. MicroRNA Regulation in Infectious Diseases and Its Potential as a Biosensor in Future Aquaculture Industry: A Review. Molecules 2023; 28:molecules28114357. [PMID: 37298833 DOI: 10.3390/molecules28114357] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2023] [Revised: 04/26/2023] [Accepted: 05/03/2023] [Indexed: 06/12/2023] Open
Abstract
An infectious disease is the most apprehensive problem in aquaculture as it can lead to high mortality in aquatic organisms and massive economic loss. Even though significant progress has been accomplished in therapeutic, prevention, and diagnostic using several potential technologies, more robust inventions and breakthroughs should be achieved to control the spread of infectious diseases. MicroRNA (miRNA) is an endogenous small non-coding RNA that post-transcriptionally regulates the protein-coding genes. It involves various biological regulatory mechanisms in organisms such as cell differentiation, proliferation, immune responses, development, apoptosis, and others. Furthermore, an miRNA also acts as a mediator to either regulate host responses or enhance the replication of diseases during infection. Therefore, the emergence of miRNAs could be potential candidates for the establishment of diagnostic tools for numerous infectious diseases. Interestingly, studies have revealed that miRNAs can be used as biomarkers and biosensors to detect diseases, and can also be used to design vaccines to attenuate pathogens. This review provides an overview of miRNA biogenesis and specifically focuses on its regulation during infection in aquatic organisms, especially on the host immune responses and how miRNAs enhance the replication of pathogens in the organism. In addition to that, we explored the potential applications, including diagnostic methods and treatments, that can be employed in the aquaculture industry.
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Affiliation(s)
- Aileen See SiouNing
- Animal Genomic and Genetics Evolutionary Laboratory, Department of Genetics and Microbiology, Institute of Biological Sciences, Faculty of Science, University of Malaya, Kuala Lumpur 50603, Malaysia
- Terra Aqua Laboratory, Centre for Research in Biotechnology for Agriculture (CEBAR), Research Management and Innovation Complex, University of Malaya, Kuala Lumpur 50603, Malaysia
| | - Tang Swee Seong
- Terra Aqua Laboratory, Centre for Research in Biotechnology for Agriculture (CEBAR), Research Management and Innovation Complex, University of Malaya, Kuala Lumpur 50603, Malaysia
- Microbial Biochemistry Laboratory, Division of Microbiology and Molecular Genetic, Institute of Biological Sciences, Faculty of Science, University of Malaya, Kuala Lumpur 50603, Malaysia
| | - Hidehiro Kondo
- Laboratory of Genome Science, Tokyo University of Marine Science and Technology, Tokyo 108-8477, Japan
| | - Subha Bhassu
- Animal Genomic and Genetics Evolutionary Laboratory, Department of Genetics and Microbiology, Institute of Biological Sciences, Faculty of Science, University of Malaya, Kuala Lumpur 50603, Malaysia
- Terra Aqua Laboratory, Centre for Research in Biotechnology for Agriculture (CEBAR), Research Management and Innovation Complex, University of Malaya, Kuala Lumpur 50603, Malaysia
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Kuz CA, Ozsahin E, Nalcacioglu R, Demirbag Z. Transcriptional Analysis of the Gene Encoding the Putative Myristoylated Membrane Protein (ORF458R) of Invertebrate Iridescent Virus 6 (IIV6). Mol Biol 2023. [DOI: 10.1134/s0026893323030056] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/06/2023]
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Kwak JS, Kim KH. Generation of Self-Inhibitory Recombinant Viral Hemorrhagic Septicemia Virus (VHSV) by Insertion of Viral P Gene-Targeting Artificial MicroRNA into Viral Genome and Effect of Dicer Gene Knockout on the Recombinant VHSV Replication. MARINE BIOTECHNOLOGY (NEW YORK, N.Y.) 2021; 23:546-559. [PMID: 34268626 DOI: 10.1007/s10126-021-10045-4] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/12/2021] [Accepted: 06/16/2021] [Indexed: 06/13/2023]
Abstract
To produce artificial microRNA (amiR)-mediated self-inhibitory viral hemorrhagic septicemia virus (VHSV), we inserted VHSV P gene-targeting amiR sequence (amiR-P) or control amiR sequence (amiR-C) between N and P genes of VHSV genome, and rescued recombinant VHSVs (rVHSV-A-amiR-P and rVHSV-A-amiR-C) using reverse genetic technology. The growth of rVHSV-A-amiR-P was significantly retarded compared to the control virus, rVHSV-A-amiR-C, due to the production of self P gene transcript-attacking microRNAs in infected cells. To enhance the replication of rVHSV-A-amiR-P, we generated the Dicer gene-knockout epithelioma papulosum cyprini (EPC-ΔDicer) cells using a CRISPR/Cas9 system, and evaluated the effect of Dicer knockout on the titer of rVHSV-A-amiR-P. The replication of rVHSV-A-amiR-C in EPC-ΔDicer cells was not different from that in control EPC cells, while the copy number of rVHSV-A-amiR-P was increasingly risen up in EPC-ΔDicer cells compared to that in control EPC cells, and the final viral titer of rVHSV-A-amiR-P was enhanced by culture in EPC-ΔDicer cells. These results indicate that VHSV can be attenuated by the equipment of self-mRNA-targeting microRNA sequence in the genome, and the titer of artificial miRNA-expressing attenuated recombinant VHSVs can be enhanced by the knockout of Dicer gene in EPC cells.
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Affiliation(s)
- Jun Soung Kwak
- Department of Aquatic Life Medicine, Pukyong National University, Busan, 48513, South Korea
| | - Ki Hong Kim
- Department of Aquatic Life Medicine, Pukyong National University, Busan, 48513, South Korea.
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Zhang XJ, Zhou L, Lu WJ, Du WX, Mi XY, Li Z, Li XY, Wang ZW, Wang Y, Duan M, Gui JF. Comparative transcriptomic analysis reveals an association of gibel carp fatty liver with ferroptosis pathway. BMC Genomics 2021; 22:328. [PMID: 33952209 PMCID: PMC8101161 DOI: 10.1186/s12864-021-07621-2] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/24/2020] [Accepted: 04/14/2021] [Indexed: 12/17/2022] Open
Abstract
BACKGROUND Fatty liver has become a main problem that causes huge economic losses in many aquaculture modes. It is a common physiological or pathological phenomenon in aquaculture, but the causes and occurring mechanism are remaining enigmatic. METHODS Each three liver samples from the control group of allogynogenetic gibel carp with normal liver and the overfeeding group with fatty liver were collected randomly for the detailed comparison of histological structure, lipid accumulation, transcriptomic profile, latent pathway identification analysis (LPIA), marker gene expression, and hepatocyte mitochondria analyses. RESULTS Compared to normal liver, larger hepatocytes and more lipid accumulation were observed in fatty liver. Transcriptomic analysis between fatty liver and normal liver showed a totally different transcriptional trajectory. GO terms and KEGG pathways analyses revealed several enriched pathways in fatty liver, such as lipid biosynthesis, degradation accumulation, peroxidation, or metabolism and redox balance activities. LPIA identified an activated ferroptosis pathway in the fatty liver. qPCR analysis confirmed that gpx4, a negative regulator of ferroptosis, was significantly downregulated while the other three positively regulated marker genes, such as acsl4, tfr1 and gcl, were upregulated in fatty liver. Moreover, the hepatocytes of fatty liver had more condensed mitochondria and some of their outer membranes were almost ruptured. CONCLUSIONS We reveal an association between ferroptosis and fish fatty liver for the first time, suggesting that ferroptosis might be activated in liver fatty. Therefore, the current study provides a clue for future studies on fish fatty liver problems.
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Affiliation(s)
- Xiao-Juan Zhang
- College of Fisheries, Huazhong Agricultural University, Wuhan, 430070, China
- State Key Laboratory of Freshwater Ecology and Biotechnology, Institute of Hydrobiology, Innovation Academy for Seed Design, Chinese Academy of Sciences, Wuhan, 430072, Hubei, China
- University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Li Zhou
- State Key Laboratory of Freshwater Ecology and Biotechnology, Institute of Hydrobiology, Innovation Academy for Seed Design, Chinese Academy of Sciences, Wuhan, 430072, Hubei, China
- University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Wei-Jia Lu
- State Key Laboratory of Freshwater Ecology and Biotechnology, Institute of Hydrobiology, Innovation Academy for Seed Design, Chinese Academy of Sciences, Wuhan, 430072, Hubei, China
- University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Wen-Xuan Du
- State Key Laboratory of Freshwater Ecology and Biotechnology, Institute of Hydrobiology, Innovation Academy for Seed Design, Chinese Academy of Sciences, Wuhan, 430072, Hubei, China
- University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Xiang-Yuan Mi
- State Key Laboratory of Freshwater Ecology and Biotechnology, Institute of Hydrobiology, Innovation Academy for Seed Design, Chinese Academy of Sciences, Wuhan, 430072, Hubei, China
- University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Zhi Li
- State Key Laboratory of Freshwater Ecology and Biotechnology, Institute of Hydrobiology, Innovation Academy for Seed Design, Chinese Academy of Sciences, Wuhan, 430072, Hubei, China
- University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Xi-Yin Li
- State Key Laboratory of Freshwater Ecology and Biotechnology, Institute of Hydrobiology, Innovation Academy for Seed Design, Chinese Academy of Sciences, Wuhan, 430072, Hubei, China
- University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Zhong-Wei Wang
- State Key Laboratory of Freshwater Ecology and Biotechnology, Institute of Hydrobiology, Innovation Academy for Seed Design, Chinese Academy of Sciences, Wuhan, 430072, Hubei, China
- University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Yang Wang
- State Key Laboratory of Freshwater Ecology and Biotechnology, Institute of Hydrobiology, Innovation Academy for Seed Design, Chinese Academy of Sciences, Wuhan, 430072, Hubei, China
- University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Ming Duan
- State Key Laboratory of Freshwater Ecology and Biotechnology, Institute of Hydrobiology, Innovation Academy for Seed Design, Chinese Academy of Sciences, Wuhan, 430072, Hubei, China
- University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Jian-Fang Gui
- College of Fisheries, Huazhong Agricultural University, Wuhan, 430070, China.
- State Key Laboratory of Freshwater Ecology and Biotechnology, Institute of Hydrobiology, Innovation Academy for Seed Design, Chinese Academy of Sciences, Wuhan, 430072, Hubei, China.
- University of Chinese Academy of Sciences, Beijing, 100049, China.
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Abo-Al-Ela HG. RNA Interference in Aquaculture: A Small Tool for Big Potential. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2021; 69:4343-4355. [PMID: 33835783 DOI: 10.1021/acs.jafc.1c00268] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
For decades, the tight regulatory functions of DNA and RNA have been the focus of extensive research with the goal of harnessing RNA molecules (e.g., microRNA and small interfering RNA) to control gene expression and to study biological functions. RNA interference (RNAi) has shown evidence of mediating gene expression, has been utilized to study functional genomics, and recently has potential in therapeutic agents. RNAi is a natural mechanism and a well-studied tool that can be used to silence specific genes. This method is also used in aquaculture as a research tool and to enhance immune responses. RNAi methods do have their limitations (e.g., immune triggering); efficient and easy-to-use RNAi methods for large-scale applications need further development. Despite these limitations, RNAi methods have been successfully used in aquaculture, in particular shrimp. This review discusses the uses of RNAi in aquaculture, such as immune- and production-related issues and the possible limitations that may hinder the application of RNAi in the aquaculture industry. Our challenge is to develop a highly potent in vivo RNAi delivery platform that could complete the desired action with minimal side effects and which can be applied on a large-scale with relatively little expense in the aquaculture industry.
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Affiliation(s)
- Haitham G Abo-Al-Ela
- Genetics and Biotechnology, Department of Aquaculture, Faculty of Fish Resources, Suez University, Suez 43518, Egypt
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8
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Rana grylio virus 43R encodes an envelope protein involved in virus entry. Virus Genes 2018; 54:779-791. [PMID: 30411182 DOI: 10.1007/s11262-018-1606-8] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2018] [Accepted: 10/06/2018] [Indexed: 12/31/2022]
Abstract
Rana grylio virus (RGV), a member of genus Ranavirus in the family Iridoviridae, is a viral pathogen infecting aquatic animal. RGV 43R has homologues only in Ranavirus and contains a transmembrane (TM) domain, but its role in RGV infection is unknown. In this study, 43R was determined to be associated with virion membrane. The transcripts encoding 43R and the protein itself appeared late in RGV-infected EPC cells and its expression was blocked by viral DNA replication inhibitor, indicating that 43R is a late expressed protein. Subcellular localization showed that 43R-EGFP fusion protein distributed in cytoplasm of EPC cells and that TM domain is essential for its distribution in cytoplasm. 43R-EGFP fusion protein colocalized with viral factories in RGV-infected cells. A recombinant RGV deleting 43R (Δ43R-RGV) was constructed by homologous recombination to investigate its role in virus infection. Compared with wild type RGV, the ability of Δ43R-RGV to induce the cytopathic effect and its virus titers were significantly reduced. Furthermore, it is revealed that 43R deletion significantly inhibited viral entry but did not influence viral DNA replication by measuring and comparing the DNA levels of RGV and Δ43R-RGV in the infected cells at the early stage of infection. RGV neutralization with anti-43R serum reduced the virus titer. Therefore, these data showed that RGV 43R is a late gene that encodes an envelope protein involved in RGV entry.
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Liu XF, Wu YH, Wei SN, Wang N, Li PF, Li YZ, Zhang NW, Qin QW, Chen SL. Establishment and characterization of a kidney cell line from kelp grouper Epinephelus moara. FISH PHYSIOLOGY AND BIOCHEMISTRY 2018; 44:87-93. [PMID: 29214431 DOI: 10.1007/s10695-017-0415-7] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/18/2017] [Accepted: 08/02/2017] [Indexed: 06/07/2023]
Abstract
A novel cell line, Epinephelus moara kidney cell line (EMK), was established from kidneys of kelp grouper E. moara. Cells were cultured at 24 °C in Leibovitz's L-15 medium (L15) supplemented with antibiotics, basic fibroblast growth factor (bFGF), foetal bovine serum (FBS) and 2-mercaptoethanol (2-ME). EMK cells, fibroblastic in morphology, proliferated to 100% confluency in 3-4 days and were subcultured for over 50 passages. The cells could grow from 18 to 30 °C, with optimal growth at 24 °C. Chromosome analysis indicated that the modal chromosome number was 48 in the cells at passage 42. Green fluorescent signals could be observed in EMK cells when the cells were transfected with pEGFP-N3 plasmid. Moreover, a significant cytopathic effect (CPE) was observed in the cells after infection with Singapore grouper iridovirus (SGIV) or nervous necrosis virus (NNV), and viral replication was confirmed by quantitative real-time PCR (qPCR). These results suggested the potential of the EMK cell line for studies of transgene and pathogenesis of SGIV and NNV.
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Affiliation(s)
- Xiao-Feng Liu
- Key Laboratory for Sustainable Development of Marine Fisheries, Ministry of Agriculture, Yellow Sea Fisheries Research Institute, CAFS, Qingdao, 266071, China
- Laboratory for Marine Fisheries Science and Food Production Processes, Qingdao National Laboratory for Marine Science and Technology, Qingdao, 266235, China
- College of Marine Life, Ocean University of China, Qingdao, 266003, China
| | - Ya-Hong Wu
- Key Laboratory for Sustainable Development of Marine Fisheries, Ministry of Agriculture, Yellow Sea Fisheries Research Institute, CAFS, Qingdao, 266071, China
| | - Shi-Na Wei
- Key Laboratory of Marine Bio-resources Sustainable Utilization, South China Sea Institute of Oceanology, Chinese Academy of Sciences, 164 West Xingang Road, Guangzhou, 510301, China
| | - Na Wang
- Key Laboratory for Sustainable Development of Marine Fisheries, Ministry of Agriculture, Yellow Sea Fisheries Research Institute, CAFS, Qingdao, 266071, China
| | - Peng-Fei Li
- Key Laboratory of Marine Bio-resources Sustainable Utilization, South China Sea Institute of Oceanology, Chinese Academy of Sciences, 164 West Xingang Road, Guangzhou, 510301, China
| | - Yang-Zhen Li
- Key Laboratory for Sustainable Development of Marine Fisheries, Ministry of Agriculture, Yellow Sea Fisheries Research Institute, CAFS, Qingdao, 266071, China
| | - Nian-Wei Zhang
- Key Laboratory for Sustainable Development of Marine Fisheries, Ministry of Agriculture, Yellow Sea Fisheries Research Institute, CAFS, Qingdao, 266071, China
| | - Qi-Wei Qin
- Key Laboratory of Marine Bio-resources Sustainable Utilization, South China Sea Institute of Oceanology, Chinese Academy of Sciences, 164 West Xingang Road, Guangzhou, 510301, China
| | - Song-Lin Chen
- Key Laboratory for Sustainable Development of Marine Fisheries, Ministry of Agriculture, Yellow Sea Fisheries Research Institute, CAFS, Qingdao, 266071, China.
- Laboratory for Marine Fisheries Science and Food Production Processes, Qingdao National Laboratory for Marine Science and Technology, Qingdao, 266235, China.
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Jia K, Yuan Y, Liu W, Liu L, Qin Q, Yi M. Identification of Inhibitory Compounds Against Singapore Grouper Iridovirus Infection by Cell Viability-Based Screening Assay and Droplet Digital PCR. MARINE BIOTECHNOLOGY (NEW YORK, N.Y.) 2018; 20:35-44. [PMID: 29209860 DOI: 10.1007/s10126-017-9785-1] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/28/2017] [Accepted: 11/20/2017] [Indexed: 06/07/2023]
Abstract
Singapore grouper iridovirus (SGIV) is one of the major causative agents of fish diseases and has caused significant economic losses in the aquaculture industry. There is currently no commercial vaccine or effective antiviral treatment against SGIV infection. Annually, an increasing number of small molecule compounds from various sources have been produced, and many are proved to be potential inhibitors against viruses. Here, a high-throughput in vitro cell viability-based screening assay was developed to identify antiviral compounds against SGIV using the luminescent-based CellTiter-Glo reagent in cultured grouper spleen cells by quantificational measurement of the cytopathic effects induced by SGIV infection. This assay was utilized to screen for potential SGIV inhibitors from five customized compounds which had been reported to be capable of inhibiting other viruses and 30 compounds isolated from various marine organisms, and three of them [ribavirin, harringtonine, and 2-hydroxytetradecanoic acid (2-HOM)] were identified to be effective on inhibiting SGIV infection, which was further confirmed with droplet digital PCR (ddPCR). In addition, the ddPCR results revealed that ribavirin and 2-HOM inhibited SGIV replication and entry in a dose-dependent manner, and harringtonine could reduce SGIV replication rather than entry at the working concentration without significant toxicity. These findings provided an easy and reliable cell viability-based screening assay to identify compounds with anti-SGIV effect and a way of studying the anti-SGIV mechanism of compounds.
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Affiliation(s)
- Kuntong Jia
- Guangdong Provincial Key Laboratory of Marine Resources and Coastal Engineering, Zhuhai Key Laboratory of Marine Bioresources and Environment, School of Marine Sciences, Sun Yat-sen University, Guangzhou, Guangdong, China
| | - Yongming Yuan
- Department of Biological Sciences, National University of Singapore, Science Drive 4, Singapore, 117543, Singapore
| | - Wei Liu
- Guangdong Provincial Key Laboratory of Marine Resources and Coastal Engineering, Zhuhai Key Laboratory of Marine Bioresources and Environment, School of Marine Sciences, Sun Yat-sen University, Guangzhou, Guangdong, China
| | - Lan Liu
- Guangdong Provincial Key Laboratory of Marine Resources and Coastal Engineering, Zhuhai Key Laboratory of Marine Bioresources and Environment, School of Marine Sciences, Sun Yat-sen University, Guangzhou, Guangdong, China
| | - Qiwei Qin
- College of Marine Sciences, South China Agricultural University, Guangzhou, 510642, China.
| | - Meisheng Yi
- Guangdong Provincial Key Laboratory of Marine Resources and Coastal Engineering, Zhuhai Key Laboratory of Marine Bioresources and Environment, School of Marine Sciences, Sun Yat-sen University, Guangzhou, Guangdong, China.
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11
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Chen ZY, Li T, Gao XC, Wang CF, Zhang QY. Protective Immunity Induced by DNA Vaccination against Ranavirus Infection in Chinese Giant Salamander Andrias davidianus. Viruses 2018; 10:v10020052. [PMID: 29364850 PMCID: PMC5850359 DOI: 10.3390/v10020052] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2017] [Revised: 01/10/2018] [Accepted: 01/24/2018] [Indexed: 12/24/2022] Open
Abstract
Andrias davidianus ranavirus (ADRV) is an emerging viral pathogen that causes severe systemic hemorrhagic disease in Chinese giant salamanders. There is an urgent need for developing an effective vaccine against this fatal disease. In this study, DNA vaccines containing the ADRV 2L gene (pcDNA-2L) and the 58L gene (pcDNA-58L) were respectively constructed, and their immune protective effects were evaluated in Chinese giant salamanders. In vitro and in vivo expression of the vaccine plasmids were confirmed in transfected cells and muscle tissues of vaccinated Chinese giant salamanders by using immunoblot analysis or RT-PCR. Following ADRV challenge, the Chinese giant salamanders vaccinated with pcDNA-2L showed a relative percent survival (RPS) of 66.7%, which was significant higher than that in Chinese giant salamanders immunized with pcDNA-58L (RPS of 3.3%). Moreover, the specific antibody against ADRV was detected in Chinese giant salamanders vaccinated with pcDNA-2L at 14 and 21 days post-vaccination by indirect enzyme-linked immunosorbent assay (ELISA). Transcriptional analysis revealed that the expression levels of immune-related genes including type I interferon (IFN), myxovirus resistance (Mx), major histocompatibility complex class IA (MHCIA), and immunoglobulin M (IgM) were strongly up-regulated after vaccination with pcDNA-2L. Furthermore, vaccination with pcDNA-2L significantly suppressed the virus replication, which was seen by a low viral load in the spleen of Chinese giant salamander survivals after ADRV challenge. These results indicated that pcDNA-2L could induce a significant innate immune response and an adaptive immune response involving both humoral and cell-mediated immunity that conferred effective protection against ADRV infection, and might be a potential vaccine candidate for controlling ADRV disease in Chinese giant salamanders.
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Affiliation(s)
- Zhong-Yuan Chen
- State Key Laboratory of Freshwater Ecology and Biotechnology, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan 430072, China.
| | - Tao Li
- State Key Laboratory of Freshwater Ecology and Biotechnology, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan 430072, China.
| | - Xiao-Chan Gao
- State Key Laboratory of Freshwater Ecology and Biotechnology, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan 430072, China.
| | - Chen-Fei Wang
- Wang's Giant Salamander Breeding Professional Cooperative, Shiyan 442013, China.
| | - Qi-Ya Zhang
- State Key Laboratory of Freshwater Ecology and Biotechnology, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan 430072, China.
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12
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Visualization of Assembly Intermediates and Budding Vacuoles of Singapore Grouper Iridovirus in Grouper Embryonic Cells. Sci Rep 2016; 6:18696. [PMID: 26727547 PMCID: PMC4698634 DOI: 10.1038/srep18696] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2015] [Accepted: 11/23/2015] [Indexed: 02/05/2023] Open
Abstract
Iridovirid infection is associated with the catastrophic loss in aquaculture industry and the population decline of wild amphibians and reptiles, but none of the iridovirid life cycles have been well explored. Here, we report the detailed visualization of the life cycle of Singapore grouper iridovirus (SGIV) in grouper cells by cryo-electron microscopy (cryoEM) and tomography (ET). EM imaging revealed that SGIV viral particles have an outer capsid layer, and the interaction of this layer with cellular plasma membrane initiates viral entry. Subsequent viral replication leads to formation of a viral assembly site (VAS), where membranous structures emerge as precursors to recruit capsid proteins to form an intermediate, double-shell, crescent-shaped structure, which curves to form icosahedral capsids. Knockdown of the major capsid protein eliminates the formation of viral capsids. As capsid formation progresses, electron-dense materials known to be involved in DNA encapsidation accumulate within the capsid until it is fully occupied. Besides the well-known budding mechanism through the cell periphery, we demonstrate a novel budding process in which viral particles bud into a tubular-like structure within vacuoles. This budding process may denote a new strategy used by SGIV to disseminate viral particles into neighbor cells while evading host immune response.
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Virus genomes and virus-host interactions in aquaculture animals. SCIENCE CHINA-LIFE SCIENCES 2015; 58:156-69. [DOI: 10.1007/s11427-015-4802-y] [Citation(s) in RCA: 130] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/15/2014] [Accepted: 10/29/2014] [Indexed: 12/20/2022]
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Virion-associated viral proteins of a Chinese giant salamander (Andrias davidianus) iridovirus (genus Ranavirus) and functional study of the major capsid protein (MCP). Vet Microbiol 2014; 172:129-39. [DOI: 10.1016/j.vetmic.2014.05.009] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2013] [Revised: 05/01/2014] [Accepted: 05/04/2014] [Indexed: 01/04/2023]
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Xie JF, Lai YX, Huang LJ, Huang RQ, Yang SW, Shi Y, Weng SP, Zhang Y, He JG. Genome-wide analyses of proliferation-important genes of Iridovirus-tiger frog virus by RNAi. Virus Res 2014; 189:214-25. [DOI: 10.1016/j.virusres.2014.05.020] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2014] [Revised: 05/21/2014] [Accepted: 05/21/2014] [Indexed: 01/09/2023]
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He LB, Ke F, Wang J, Gao XC, Zhang QY. Rana grylio virus (RGV) envelope protein 2L: subcellular localization and essential roles in virus infectivity revealed by conditional lethal mutant. J Gen Virol 2014; 95:679-690. [DOI: 10.1099/vir.0.058776-0] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023] Open
Abstract
Rana grylio virus (RGV) is a pathogenic iridovirus that has resulted in high mortality in cultured frog. Here, an envelope protein gene, 2L, was identified from RGV and its possible role in virus infection was investigated. Database searches found that RGV 2L had homologues in all sequenced iridoviruses and is a core gene of iridoviruses. Western blotting detection of purified RGV virions confirmed that 2L protein was associated with virion membrane. Fluorescence localization revealed that 2L protein co-localized with viral factories in RGV infected cells. In co-transfected cells, 2L protein co-localized with two other viral envelope proteins, 22R and 53R. However, 2L protein did not co-localize with the major capsid protein of RGV in co-transfected cells. Meanwhile, fluorescence observation showed that 2L protein co-localized with endoplasmic reticulum, but did not co-localize with mitochondria and Golgi apparatus. Moreover, a conditional lethal mutant virus containing the lac repressor/operator system was constructed to investigate the role of RGV 2L in virus infection. The ability to form plaques and the virus titres were strongly reduced when expression of 2L was repressed. Therefore, the current data showed that 2L protein is essential for virus infection. Our study is the first report, to our knowledge, of co-localization between envelope proteins in iridovirus and provides new insights into the understanding of envelope proteins in iridovirus.
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Affiliation(s)
- Li-Bo He
- State Key Laboratory of Freshwater Ecology and Biotechnology, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan 430072, PR China
| | - Fei Ke
- State Key Laboratory of Freshwater Ecology and Biotechnology, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan 430072, PR China
| | - Jun Wang
- State Key Laboratory of Freshwater Ecology and Biotechnology, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan 430072, PR China
| | - Xiao-Chan Gao
- State Key Laboratory of Freshwater Ecology and Biotechnology, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan 430072, PR China
| | - Qi-Ya Zhang
- State Key Laboratory of Freshwater Ecology and Biotechnology, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan 430072, PR China
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Huang X, Gong J, Huang Y, Ouyang Z, Wang S, Chen X, Qin Q. Characterization of an envelope gene VP19 from Singapore grouper iridovirus. Virol J 2013; 10:354. [PMID: 24341864 PMCID: PMC3878628 DOI: 10.1186/1743-422x-10-354] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2013] [Accepted: 12/11/2013] [Indexed: 01/22/2023] Open
Abstract
Background Viral envelope proteins are always proposed to exert important function during virus infection and replication. Vertebrate iridoviruses are enveloped large DNA virus, which can cause great economic losses in aquaculture and ecological destruction. Although numerous iridovirus envelope proteins have been identified using bioinformatics and proteomic methods, their roles in virus infection remained largely unknown. Methods Using SMART and TMHMM programs, we investigated the structural characteristics of Singapore grouper iridovirus (SGIV) VP19. A specific antibody against VP19 was generated and the expression profile of VP19 was clarified. The subcellular localization of VP19 in the absence or presence of other viral products was determined via transfection and immune fluorescence assay. In addition, Western blot assay and electron microscopy examination were performed to demonstrate whether SGIV VP19 was an envelope protein or a capsid protein. Results Here, SGIV VP19 was cloned and characterized. Among all sequenced iridoviruses, VP19 and its orthologues shared common features, including 19 invariant cysteines, a proline-rich motif and a predicted transmembrane domain. Subsequently, the protein synthesis of VP19 was only detected at the late stage of SGIV infection and inhibited obviously by treating with AraC, confirming that VP19 was a late expressed protein. Ectopic expression of EGFP-VP19 in vitro displayed a punctate pattern in the cytoplasm. In SGIV infected cells, the newly synthesized VP19 protein was initially localized in the cytoplasm in a punctate pattern, and then aggregated into the virus assembly site at the late stage of SGIV infection, suggesting that other viral protein products were essential for VP19’s function during SGIV infection. In addition, Western blot assay and electron microscopy observation revealed that SGIV VP19 was associated with viral envelope, which was different from major capsid protein (MCP). Conclusion Taken together, the current data suggested that VP19 represented a conserved envelope protein in iridovirus, and might contribute greatly to virus assembly during virus infection.
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Affiliation(s)
| | | | | | | | | | | | - Qiwei Qin
- Key Laboratory of Tropical Marine Bio-resources and Ecology, South China Sea Institute of Oceanology, Chinese Academy of Sciences, 164 West Xingang Road, Guangzhou 510301, China.
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He LB, Gao XC, Ke F, Zhang QY. A conditional lethal mutation in Rana grylio virus ORF 53R resulted in a marked reduction in virion formation. Virus Res 2013; 177:194-200. [DOI: 10.1016/j.virusres.2013.07.016] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2013] [Revised: 07/19/2013] [Accepted: 07/22/2013] [Indexed: 01/07/2023]
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19
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Genome architecture changes and major gene variations of Andrias davidianus ranavirus (ADRV). Vet Res 2013; 44:101. [PMID: 24143877 PMCID: PMC4015033 DOI: 10.1186/1297-9716-44-101] [Citation(s) in RCA: 52] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2013] [Accepted: 10/04/2013] [Indexed: 01/08/2023] Open
Abstract
Ranaviruses are emerging pathogens that have led to global impact and public concern. As a rarely endangered species and the largest amphibian in the world, the Chinese giant salamander, Andrias davidianus, has recently undergone outbreaks of epidemic diseases with high mortality. In this study, we isolated and identified a novel ranavirus from the Chinese giant salamanders that exhibited systemic hemorrhage and swelling syndrome with high death rate in China during May 2011 to August 2012. The isolate, designated Andrias davidianus ranavirus (ADRV), not only could induce cytopathic effects in different fish cell lines and yield high viral titers, but also caused severely hemorrhagic lesions and resulted in 100% mortality in experimental infections of salamanders. The complete genome of ADRV was sequenced and compared with other sequenced amphibian ranaviruses. Gene content and phylogenetic analyses revealed that ADRV should belong to an amphibian subgroup in genus Ranavirus, and is more closely related to frog ranaviruses than to other salamander ranaviruses. Homologous gene comparisons show that ADRV contains 99%, 97%, 94%, 93% and 85% homologues in RGV, FV3, CMTV, TFV and ATV genomes respectively. In addition, several variable major genes, such as duplicate US22 family-like genes, viral eukaryotic translation initiation factor 2 alpha gene and novel 75L gene with both motifs of nuclear localization signal (NLS) and nuclear export signal (NES), were predicted to contribute to pathogen virulence and host susceptibility. These findings confirm the etiologic role of ADRV in epidemic diseases of Chinese giant salamanders, and broaden our understanding of evolutionary emergence of ranaviruses.
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Ke F, He LB, Zhang QY. Nonstructural protein NS80 is crucial in recruiting viral components to form aquareoviral factories. PLoS One 2013; 8:e63737. [PMID: 23671697 PMCID: PMC3646018 DOI: 10.1371/journal.pone.0063737] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2012] [Accepted: 04/10/2013] [Indexed: 11/21/2022] Open
Abstract
Background Replication and assembly of vertebrate reoviruses occur in specific intracellular compartments known as viral factories. Recently, NS88 and NS80, the nonstructural proteins from aquareoviruses, have been proposed to share common traits with µNS from orthoreoviruses, which are involved in the formation of viral factories. Methodology/Principal Findings In this study, the NS80 characteristics and its interactions with other viral components were investigated. We observed that the NS80 structure ensured its self-aggregation and selective recruitment of viral proteins to viral factories like structures (VFLS). The minimum amino acids (aa) of NS80 required for VFLS formation included 193 aa at the C-terminal. However, this truncated protein only contained one aa coil and located in the nucleus. Its N-terminal residual regions, aa 1–55 and aa 55–85, were required for recruiting viral nonstructural protein NS38 and structural protein VP3, respectively. A conserved N-terminal region of NS38, which was responsible for the interaction with NS80, was also identified. Moreover, the minimal region of C-terminal residues, aa 506–742 (Δ505), required for NS80 self-aggregation in the cytoplasm, and aa 550–742 (Δ549), which are sufficient for recruiting viral structure proteins VP1, VP2, and VP4 were also identified. Conclusions/Significance The present study shows detailed interactions between NS80 and NS38 or other viral proteins. Sequence and structure characteristics of NS80 ensures its self-aggregation to form VFLS (either in the cytoplasm or nucleus) and recruitment of viral structural or nonstructural proteins.
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Affiliation(s)
- Fei Ke
- State Key Laboratory of Freshwater Ecology and Biotechnology, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan, China
| | - Li-Bo He
- State Key Laboratory of Freshwater Ecology and Biotechnology, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan, China
| | - Qi-Ya Zhang
- State Key Laboratory of Freshwater Ecology and Biotechnology, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan, China
- * E-mail:
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Lima PC, Harris JO, Cook M. Exploring RNAi as a therapeutic strategy for controlling disease in aquaculture. FISH & SHELLFISH IMMUNOLOGY 2013; 34:729-743. [PMID: 23276883 DOI: 10.1016/j.fsi.2012.11.037] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/29/2012] [Revised: 11/21/2012] [Accepted: 11/30/2012] [Indexed: 06/01/2023]
Abstract
Aquatic animal diseases are one of the most significant constraints to the development and management of aquaculture worldwide. As a result, measures to combat diseases of fish and shellfish have assumed a high priority in many aquaculture-producing countries. RNA interference (RNAi), a natural mechanism for post-transcriptional silencing of homologous genes by double-stranded RNA (dsRNA), has emerged as a powerful tool not only to investigate the function of specific genes, but also to suppress infection or replication of many pathogens that cause severe economic losses in aquaculture. However, despite the enormous potential as a novel therapeutical approach, many obstacles must still be overcome before RNAi therapy finds practical application in aquaculture, largely due to the potential for off-target effects and the difficulties in providing safe and effective delivery of RNAi molecules in vivo. In the present review, we discuss the current knowledge of RNAi as an experimental tool, as well as the concerns and challenges ahead for the application of such technology to combat infectious disease of farmed aquatic animals.
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Affiliation(s)
- Paula C Lima
- CSIRO Marine and Atmospheric Research, C/-CSIRO Livestock Industries, QBP, 306 Carmody Rd, St Lucia, QLD 4067, Australia
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Clarke BD, Cummins DM, McColl KA, Ward AC, Doran TJ. Characterization of zebrafish polymerase III promoters for the expression of short-hairpin RNA interference molecules. Zebrafish 2012; 10:472-9. [PMID: 23030845 DOI: 10.1089/zeb.2012.0782] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
RNA interference (RNAi) is a powerful, sequence specific, and long-lasting method of gene knockdown, and can be elicited by the expression of short-hairpin RNA (shRNA) molecules driven via polymerase III type 3 promoters from a DNA vector or transgene. To further develop RNAi as a tool in zebrafish, we have characterized the zebrafish U6 and H1 snRNA promoters and compared the efficiency of each of the promoters to express an shRNA and silence a reporter gene, relative to previously characterized U6 promoters from pufferfish, chicken, and mouse. Our results show that the zebrafish polymerase III promoters were capable of effective gene silencing in the zebrafish ZF4 cell line, but were ineffective in mammalian Vero cells. In contrast, mouse and chicken promoters were active in Vero but not ZF4 cells, highlighting the importance of homologous promoters to achieve effective silencing.
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Affiliation(s)
- Brian D Clarke
- 1 CSIRO Livestock Industries, Australian Animal Health Laboratory, Geelong , Victoria, Australia
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Lei XY, Ou T, Zhang QY. Rana grylio virus (RGV) 50L is associated with viral matrix and exhibited two distribution patterns. PLoS One 2012; 7:e43033. [PMID: 22912781 PMCID: PMC3418244 DOI: 10.1371/journal.pone.0043033] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2012] [Accepted: 07/16/2012] [Indexed: 12/24/2022] Open
Abstract
BACKGROUND The complete genome of Rana grylio virus (RGV) was sequenced and analyzed recently, which revealed that RGV 50 L had homologues in many iridoviruses with different identities; however, the characteristics and functions of 50 L have not been studied yet. METHODOLOGY/PRINCIPAL FINDINGS We cloned and characterized RGV50L, and revealed 50 L functions in virus assembly and gene regulation. 50 L encoded a 499-amino acid structural protein of about 85 kDa in molecular weight and contained a nuclear localization signal (NLS) and a helix- extension-helix motif. Drug inhibition assay demonstrated that 50 L was an immediate-early (IE) gene. Immuno-fluorescence assay revealed that 50 L appeared early and persisted in RGV-infected cells following two distribution patterns. One pattern was that 50 L exhibited a cytoplasm-nucleus- viromatrix distribution pattern, and mutagenesis of the NLS motif revealed that localization of 50 L in the nucleus was NLS-dependent; the other was that 50 L co-localized with viral matrix which plays important roles in virus assembly and the life circle of viruses. CONCLUSIONS/SIGNIFICANCE RGV 50L is a novel iridovirus IE gene encoded structural protein which plays important roles in virus assembly.
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Affiliation(s)
- Xiao-Ying Lei
- State Key Laboratory of Freshwater Ecology and Biotechnology, Institute of Hydrobiology, Chinese Academy of Sciences, Graduate School of the Chinese Academy of Sciences, Wuhan, China
| | - Tong Ou
- State Key Laboratory of Freshwater Ecology and Biotechnology, Institute of Hydrobiology, Chinese Academy of Sciences, Graduate School of the Chinese Academy of Sciences, Wuhan, China
| | - Qi-Ya Zhang
- State Key Laboratory of Freshwater Ecology and Biotechnology, Institute of Hydrobiology, Chinese Academy of Sciences, Graduate School of the Chinese Academy of Sciences, Wuhan, China
- * E-mail:
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Application of RNA silencing to plant disease resistance. SILENCE 2012; 3:5. [PMID: 22650989 PMCID: PMC3503840 DOI: 10.1186/1758-907x-3-5] [Citation(s) in RCA: 110] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/22/2012] [Accepted: 04/27/2012] [Indexed: 01/23/2023]
Abstract
To reduce the losses caused by plant pathogens, plant biologists have adopted numerous methods to engineer resistant plants. Among them, RNA silencing-based resistance has been a powerful tool that has been used to engineer resistant crops during the last two decades. Based on this mechanism, diverse approaches were developed. In this review, we focus on the application of RNA silencing to produce plants that are resistant to plant viruses such as RNA and DNA viruses, viroids, insects, and the recent expansion to fungal pathogens.
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Lei XY, Ou T, Zhu RL, Zhang QY. Sequencing and analysis of the complete genome of Rana grylio virus (RGV). Arch Virol 2012; 157:1559-64. [DOI: 10.1007/s00705-012-1316-9] [Citation(s) in RCA: 47] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2012] [Accepted: 03/19/2012] [Indexed: 12/29/2022]
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Li S, Sun F, Zhang YB, Gui JF, Zhang QY. Identification of DreI as an antiviral factor regulated by RLR signaling pathway. PLoS One 2012; 7:e32427. [PMID: 22412872 PMCID: PMC3296712 DOI: 10.1371/journal.pone.0032427] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2011] [Accepted: 01/26/2012] [Indexed: 12/21/2022] Open
Abstract
Background Retinoic acid-inducible gene I (RIG-I)–like receptors (RLRs) had been demonstrated to prime interferon (IFN) response against viral infection via the conserved RLR signaling in fish, and a novel fish-specific gene, the grass carp reovirus (GCRV)-induced gene 2 (Gig2), had been suggested to play important role in host antiviral response. Methodology/Principal Findings In this study, we cloned and characterized zebrafish Gig2 homolog (named Danio rerio Gig2-I, DreI), and revealed its antiviral role and expressional regulation signaling pathway. RT-PCR, Western blot and promoter activity assay indicate that DreI can be induced by poly I:C, spring viremia of carp virus (SVCV) and recombinant IFN (rIFN), showing that DreI is a typical ISG. Using the pivotal signaling molecules of RLR pathway, including RIG-I, MDA5 and IRF3 from crucian carp, it is found that DreI expression is regulated by RLR cascade and IRF3 plays an important role in this regulation. Furthermore, promoter mutation assay confirms that the IFN-stimulated regulatory elements (ISRE) in the 5′ flanking region of DreI is essential for its induction. Finally, overexpression of DreI leads to establish a strong antiviral state against SVCV and Rana grylio virus (RGV) infection in EPC (Epithelioma papulosum cyprinid) cells. Conclusions/Significance These data indicate that DreI is an antiviral protein, which is regulated by RLR signaling pathway.
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Affiliation(s)
| | | | | | | | - Qi-Ya Zhang
- State Key Laboratory of Freshwater Ecology and Biotechnology, Wuhan Center for Developmental Biology, Institute of Hydrobiology, Graduate School of the Chinese Academy of Sciences, Chinese Academy of Sciences, Wuhan, China
- * E-mail:
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Fattash I, Khraiwesh B, Arif MA, Frank W. Expression of artificial microRNAs in Physcomitrella patens. METHODS IN MOLECULAR BIOLOGY (CLIFTON, N.J.) 2012; 847:293-315. [PMID: 22351018 DOI: 10.1007/978-1-61779-558-9_25] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
MicroRNAs (miRNAs) are ∼21-nt-long small RNAs transcribed from endogenous MIR genes which form precursor RNAs with a characteristic hairpin structure. MiRNAs control the expression of cognate target genes by binding to reverse complementary sequences resulting in cleavage or translational inhibition of the target RNA. Artificial miRNAs (amiRNAs) can be generated by exchanging the miRNA/miRNA sequence of endogenous MIR precursor genes, while maintaining the general pattern of matches and mismatches in the foldback. Thus, for functional gene analysis, amiRNAs can be designed to target any gene of interest. During the last decade, the moss Physcomitrella patens emerged as a model plant for functional gene analysis based on its unique ability to integrate DNA into the nuclear genome by homologous recombination which allows for the generation targeted gene knockout mutants. In addition to this, we developed a protocol to express amiRNAs in P. patens that has particular advantages over the generation of knockout mutants and might be used to speed up reverse genetics approaches in this model species.
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Affiliation(s)
- Isam Fattash
- Plant Biotechnology, Faculty of Biology, University of Freiburg, Freiburg, Germany
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Xiong XP, Dong CF, Weng SP, Zhang J, Zhang Y, He JG. Antigenic identification of virion structural proteins from infectious spleen and kidney necrosis virus. FISH & SHELLFISH IMMUNOLOGY 2011; 31:919-924. [PMID: 21888976 DOI: 10.1016/j.fsi.2011.08.009] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/14/2010] [Revised: 08/05/2011] [Accepted: 08/19/2011] [Indexed: 05/31/2023]
Abstract
Infectious spleen and kidney necrosis virus (ISKNV), belonging to the genus Megalocytivirus in the family Iridoviridae, is one of the major agents causing mortality and economic losses to the freshwater fish culture industry in Asian countries. Currently, little information regarding the antigenic properties of Megalocytivirus (especially ISKNV) is available. Our previous study using four different workflows with systematic and comprehensive proteomic approaches led to the identification of 38 ISKNV virion-associated proteins (J. Virol. 2869-2877, 2011). Thus, in this report, the antigenicity of 31 structural proteins from ISKNV virion was investigated. A one-dimensional gel electrophoresis immunoblot profile coupled with MALDI-TOF-TOF MS/MS was applied to identify six immunogenic viral proteins, namely, ORFs major capsid protein (006L), 054L, 055L, 101L, 117L, and 125L. Then, the antigenicity of 31 structural proteins was characterized by Western blot by using pooled sera from mandarin fish that survived ISKNV infection. Of the 31 viral proteins, 22 were recognized by the fish ISKNV antiserum. Furthermore, this antiserum neutralizes MFF-1 cells ISKNV infection. To our knowledge, this study is the first report on the immunogenicity of viral proteins and characterization of the proteome of megalocytivirus infective agents. Our findings are expected to promote the development of effective vaccine candidates.
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Affiliation(s)
- Xiao-Peng Xiong
- State Key Laboratory of Biocontrol, School of Life Sciences, Sun Yat-sen University, 135 Xingang West Road, Guangzhou 510275, People's Republic of China
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A novel cyanophage with a cyanobacterial nonbleaching protein A gene in the genome. J Virol 2011; 86:236-45. [PMID: 22031930 DOI: 10.1128/jvi.06282-11] [Citation(s) in RCA: 62] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
A cyanophage, PaV-LD, has been isolated from harmful filamentous cyanobacterium Planktothrix agardhii in Lake Donghu, a shallow freshwater lake in China. Here, we present the cyanophage's genomic organization and major structural proteins. The genome is a 95,299-bp-long, linear double-stranded DNA and contains 142 potential genes. BLAST searches revealed 29 proteins of known function in cyanophages, cyanobacteria, or bacteria. Thirteen major structural proteins ranging in size from 27 kDa to 172 kDa were identified by SDS-PAGE and mass-spectrometric analysis. The genome lacks major genes that are necessary to the tail structure, and the tailless PaV-LD has been confirmed by an electron microscopy comparison with other tail cyanophages and phages. Phylogenetic analysis of the major capsid proteins also reveals an independent branch of PaV-LD that is quite different from other known tail cyanophages and phages. Moreover, the unique genome carries a nonbleaching protein A (NblA) gene (open reading frame [ORF] 022L), which is present in all phycobilisome-containing organisms and mediates phycobilisome degradation. Western blot detection confirmed that 022L was expressed after PaV-LD infection in the host filamentous cyanobacterium. In addition, its appearance was companied by a significant decline of phycocyanobilin content and a color change of the cyanobacterial cells from blue-green to yellow-green. The biological function of PaV-LD nblA was further confirmed by expression in a model cyanobacterium via an integration platform, by spectroscopic analysis and electron microscopy observation. The data indicate that PaV-LD is an exceptional cyanophage of filamentous cyanobacteria, and this novel cyanophage will also provide us with a new vision of the cyanophage-host interactions.
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Chinchar VG, Yu KH, Jancovich JK. The molecular biology of frog virus 3 and other iridoviruses infecting cold-blooded vertebrates. Viruses 2011; 3:1959-85. [PMID: 22069524 PMCID: PMC3205390 DOI: 10.3390/v3101959] [Citation(s) in RCA: 89] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2011] [Revised: 09/27/2011] [Accepted: 09/27/2011] [Indexed: 01/01/2023] Open
Abstract
Frog virus 3 (FV3) is the best characterized member of the family Iridoviridae. FV3 study has provided insights into the replication of other family members, and has served as a model of viral transcription, genome replication, and virus-mediated host-shutoff. Although the broad outlines of FV3 replication have been elucidated, the precise roles of most viral proteins remain unknown. Current studies using knock down (KD) mediated by antisense morpholino oligonucleotides (asMO) and small, interfering RNAs (siRNA), knock out (KO) following replacement of the targeted gene with a selectable marker by homologous recombination, ectopic viral gene expression, and recombinant viral proteins have enabled researchers to systematically ascertain replicative- and virulence-related gene functions. In addition, the application of molecular tools to ecological studies is providing novel ways for field biologists to identify potential pathogens, quantify infections, and trace the evolution of ecologically important viral species. In this review, we summarize current studies using not only FV3, but also other iridoviruses infecting ectotherms. As described below, general principles ascertained using FV3 served as a model for the family, and studies utilizing other ranaviruses and megalocytiviruses have confirmed and extended our understanding of iridovirus replication. Collectively, these and future efforts will elucidate molecular events in viral replication, intrinsic and extrinsic factors that contribute to disease outbreaks, and the role of the host immune system in protection from disease.
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Affiliation(s)
- V Gregory Chinchar
- Department of Microbiology, University of Mississippi Medical Center, 2500 N. State Street, Jackson, MS 39216, USA.
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He LB, Ke F, Zhang QY. Rana grylio virus as a vector for foreign gene expression in fish cells. Virus Res 2011; 163:66-73. [PMID: 21889962 DOI: 10.1016/j.virusres.2011.08.012] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2011] [Revised: 08/16/2011] [Accepted: 08/18/2011] [Indexed: 01/25/2023]
Abstract
In the present study, Rana grylio virus (RGV, an iridovirus) thymidine kinase (TK) gene and viral envelope protein 53R gene were chosen as targets for foreign gene insertion. ΔTK-RGV and Δ53R-RGV, two recombinant RGV, expressing enhanced green fluorescence protein (EGFP) were constructed and analyzed in Epithelioma papulosum cyprinid (EPC) cells. The EGFP gene which fused to the virus major capsid protein (MCP) promoter p50 was inserted into TK and 53R gene loci of RGV, respectively. Cells infected with these two recombinant viruses not only displayed plaques, but also emitted strong green fluorescence under fluorescence microscope, providing a simple method for selection and purification of recombinant viruses. ΔTK-RGV was purified by seven successive rounds of plaque isolation and could be stably propagated in EPC cells. All of the plaques produced by the purified recombinant virus emitted green fluorescence. However, Δ53R-RGV was hard to be purified even through twenty rounds of plaque isolation. The purified recombinant virus ΔTK-RGV was verified by PCR analysis and Western blotting. These results showed EGFP was expressed in ΔTK-RGV infected cells. Furthermore, one-step growth curves and electron microscopy revealed that infection with recombinant ΔTK-RGV and wild-type RGV are similar. Therefore, RGV was demonstrated could be as a viral vector for foreign gene expression in fish cells.
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Affiliation(s)
- Li-Bo He
- State Key Laboratory of Freshwater Ecology and Biotechnology, Institute of Hydrobiology, Chinese Academy of Sciences, Graduate School of the Chinese Academy of Sciences, Wuhan 430072, China
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Huang Y, Huang X, Cai J, Ye F, Guan L, Liu H, Qin Q. Construction of green fluorescent protein-tagged recombinant iridovirus to assess viral replication. Virus Res 2011; 160:221-9. [PMID: 21756948 DOI: 10.1016/j.virusres.2011.06.018] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2011] [Revised: 06/19/2011] [Accepted: 06/22/2011] [Indexed: 12/25/2022]
Abstract
Green fluorescent protein-tagged recombinant virus has been successfully applied to observing the infective dynamics and evaluating viral replication. Here, we identified soft-shelled turtle iridovirus (STIV) ORF55 as an envelope protein (VP55), and developed a recombinant STIV expressing an enhanced green fluorescent protein (EGFP) fused to VP55 (EGFP-STIV). Recombinant EGFP-STIV shared similar single-step growth curves and ultrastructural morphology with wild type STIV (wt-STIV). The green fluorescence distribution during EGFP-STIV infection was consistent with the intracellular distribution of VP55 which was mostly co-localized with virus assembly sites. Furthermore, EGFP-STIV could be used to evaluate viral replication conveniently under drug treatment, and the result showed that STIV replication was significantly inhibited after the addition of antioxidant pyrrolidine dithiocarbamate (PDTC). Thus, the EGFP-tagged recombinant iridovirus will not only be useful for further investigations on the viral replicative dynamics, but also provide an alternative simple strategy to screen for antiviral substances.
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Affiliation(s)
- Youhua Huang
- Key Laboratory of Marine Bio-resources Sustainable Utilization, South China Sea Institute of Oceanology, Chinese Academy of Sciences, 164 West Xingang Road, Guangzhou 510301, PR China
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