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Ariza ME, Cox B, Martinez B, Mena-palomo I, Zarate GJ, Williams MV. Viral dUTPases: Modulators of Innate Immunity. Biomolecules 2022; 12:227. [PMID: 35204728 PMCID: PMC8961515 DOI: 10.3390/biom12020227] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2021] [Revised: 01/24/2022] [Accepted: 01/26/2022] [Indexed: 11/17/2022] Open
Abstract
Most free-living organisms encode for a deoxyuridine triphosphate nucleotidohydrolase (dUTPase; EC 3.6.1.23). dUTPases represent a family of metalloenzymes that catalyze the hydrolysis of dUTP to dUMP and pyrophosphate, preventing dUTP from being incorporated into DNA by DNA polymerases, maintaining a low dUTP/dTTP pool ratio and providing a necessary precursor for dTTP biosynthesis. Thus, dUTPases are involved in maintaining genomic integrity by preventing the uracilation of DNA. Many DNA-containing viruses, which infect mammals also encode for a dUTPase. This review will summarize studies demonstrating that, in addition to their classical enzymatic activity, some dUTPases possess novel functions that modulate the host innate immune response.
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Zang K, Li F, Ma Q. The dUTPase of white spot syndrome virus assembles its active sites in a noncanonical manner. J Biol Chem 2017; 293:1088-1099. [PMID: 29187596 DOI: 10.1074/jbc.m117.815266] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2017] [Revised: 11/14/2017] [Indexed: 01/04/2023] Open
Abstract
dUTPases are essential enzymes for maintaining genome integrity and have recently been shown to play moonlighting roles when containing extra sequences. Interestingly, the trimeric dUTPase of white spot syndrome virus (wDUT) harbors a sequence insert at the position preceding the C-terminal catalytic motif V (pre-V insert), rarely seen in other dUTPases. However, whether this extra sequence endows wDUT with additional properties is unknown. Herein, we present the crystal structures of wDUT in both ligand-free and ligand-bound forms. We observed that the pre-V insert in wDUT forms an unusual β-hairpin structure in the domain-swapping region and thereby facilitates a unique orientation of the adjacent C-terminal segment, positioning the catalytic motif V onto the active site of its own subunit instead of a third subunit. Consequently, wDUT employs two-subunit active sites, unlike the widely accepted paradigm that the active site of trimeric dUTPase is contributed by all three subunits. According to results from local structural comparisons, the active-site configuration of wDUT is similar to that of known dUTPases. However, we also found that residues in the second-shell region of the active site are reconfigured in wDUT as an adaption to its unique C-terminal orientation. We also show that deletion of the pre-V insert significantly reduces wDUT's enzymatic activity and thermal stability. We hypothesize that this rare structural arrangement confers additional functionality to wDUT. In conclusion, our study expands the structural diversity in the conserved dUTPase family and illustrates how sequence insertion and amino acid substitution drive protein evolution cooperatively.
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Affiliation(s)
- Kun Zang
- From the Key Laboratory of Experimental Marine Biology, Institute of Oceanology, Chinese Academy of Sciences, Nanhai Road 7, Qingdao 266071, China.,the Laboratory for Marine Biology and Biotechnology, Qingdao National Laboratory for Marine Science and Technology, Qingdao 266237, China, and.,the University of Chinese Academy of Sciences, Beijing 100049, China
| | - Fuhua Li
- From the Key Laboratory of Experimental Marine Biology, Institute of Oceanology, Chinese Academy of Sciences, Nanhai Road 7, Qingdao 266071, China.,the Laboratory for Marine Biology and Biotechnology, Qingdao National Laboratory for Marine Science and Technology, Qingdao 266237, China, and
| | - Qingjun Ma
- From the Key Laboratory of Experimental Marine Biology, Institute of Oceanology, Chinese Academy of Sciences, Nanhai Road 7, Qingdao 266071, China, .,the Laboratory for Marine Biology and Biotechnology, Qingdao National Laboratory for Marine Science and Technology, Qingdao 266237, China, and
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Rozenberg A, Brand P, Rivera N, Leese F, Schubart CD. Characterization of fossilized relatives of the White Spot Syndrome Virus in genomes of decapod crustaceans. BMC Evol Biol 2015; 15:142. [PMID: 26187050 PMCID: PMC4506587 DOI: 10.1186/s12862-015-0380-7] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2015] [Accepted: 05/13/2015] [Indexed: 11/10/2022] Open
Abstract
Background The White Spot Syndrome Virus (WSSV) is an important pathogen that infects a variety of decapod species and causes a highly contagious disease in penaeid shrimps. Mass mortalities caused by WSSV have pronounced commercial impact on shrimp aquaculture. Until now WSSV is the only known member of the virus family Nimaviridae, a group with obscure phylogenetic affinities. Its isolated position makes WSSV studies challenging due to large number of genes without homology in other viruses or cellular organisms. Results Here we report the discovery of an unusually large amount of sequences with high similarity to WSSV in a genomic library from the Jamaican bromeliad crab Metopaulias depressus. De novo assembly of these sequences allowed for the partial reconstruction of the genome of this endogenized virus with total length of 200 kbp encompassed in three scaffolds. The genome includes at least 68 putative open reading frames with homology in WSSV, most of which are intact. Among these, twelve orthologs of WSSV genes coding for non-structural proteins and nine genes known to code for the major components of the WSSV virion were discovered. Together with reanalysis of two similar cases of WSSV-like sequences in penaeid shrimp genomic libraries, our data allowed comparison of gene composition and gene order between different lineages related to WSSV. Furthermore, screening of published sequence databases revealed sequences with highest similarity to WSSV and the newly described virus in genomic libraries of at least three further decapod species. Analysis of the viral sequences detected in decapods suggests that they are less a result of contemporary WSSV infection, but rather originate from ancestral infection events. Phylogenetic analyses suggest that genes were acquired repeatedly by divergent viruses or viral strains of the Nimaviridae. Conclusions Our results shed new light on the evolution of the Nimaviridae and point to a long association of this viral group with decapod crustaceans. Electronic supplementary material The online version of this article (doi:10.1186/s12862-015-0380-7) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Andrey Rozenberg
- Ruhr University Bochum, Department of Animal Ecology, Evolution and Biodiversity, Bochum, Germany.
| | - Philipp Brand
- Ruhr University Bochum, Department of Animal Ecology, Evolution and Biodiversity, Bochum, Germany. .,University of California, Davis, Department of Evolution and Ecology, Center for Population Biology, Davis, USA.
| | - Nicole Rivera
- University of Regensburg, Department of Zoology and Evolutionary Biology, Regensburg, Germany.
| | - Florian Leese
- Ruhr University Bochum, Department of Animal Ecology, Evolution and Biodiversity, Bochum, Germany.
| | - Christoph D Schubart
- University of Regensburg, Department of Zoology and Evolutionary Biology, Regensburg, Germany.
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Segarra A, Faury N, Pépin JF, Renault T. Transcriptomic study of 39 ostreid herpesvirus 1 genes during an experimental infection. J Invertebr Pathol 2014; 119:5-11. [PMID: 24681357 DOI: 10.1016/j.jip.2014.03.002] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2013] [Revised: 03/17/2014] [Accepted: 03/18/2014] [Indexed: 12/29/2022]
Abstract
Massive mortality outbreaks have been reported in France since 2008 among Pacific oysters, Crassostrea gigas, with the detection of a particular OsHV-1 variant called μVar. Virus infection can be induced in healthy spat in experimental conditions allowing to better understand the disease process, including viral gene expression. Although gene expression of other herpesviruses has been widely studied, we provide the first study following viral gene expression of OsHV-1 over time. In this context, an in vivo transcriptomic study targeting 39 OsHV-1 genes was carried out during an experimental infection of Pacific oyster spat. For the first time, several OsHV-1 mRNAs were detected by real-time PCR at 0 h, 2 h, 4 h, 18 h, 26 h and 42 h post-injection. Several transcripts were detected at 2h post-infection and at 18 h post-infection for all selected ORFs. Quantification of virus gene expression at different times of infection was also carried out using an oyster housekeeping gene, Elongation factor. Developing an OsHV-1-specific reverse transcriptase real time PCR targeting 39 viral gene appears a new tool in terms of diagnosis and can be used to complement viral DNA detection in order to monitor viral replication.
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Affiliation(s)
- Amélie Segarra
- Ifremer (Institut Français de Recherche pour l'Exploitation de la Mer), Unité Santé, Génétique et Microbiologie des Mollusques (SG2M), Laboratoire de Génétique et Pathologie des Mollusques Marins (LGPMM), Avenue de Mus de Loup, 17390 La Tremblade, France
| | - Nicole Faury
- Ifremer (Institut Français de Recherche pour l'Exploitation de la Mer), Unité Santé, Génétique et Microbiologie des Mollusques (SG2M), Laboratoire de Génétique et Pathologie des Mollusques Marins (LGPMM), Avenue de Mus de Loup, 17390 La Tremblade, France
| | - Jean-François Pépin
- Ifremer, Laboratoire Environnement Ressources des Pertuis Charentais (LERPC), Avenue de Mus de Loup, 17390 La Tremblade, France
| | - Tristan Renault
- Ifremer (Institut Français de Recherche pour l'Exploitation de la Mer), Unité Santé, Génétique et Microbiologie des Mollusques (SG2M), Laboratoire de Génétique et Pathologie des Mollusques Marins (LGPMM), Avenue de Mus de Loup, 17390 La Tremblade, France.
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Ran X, Bian X, Ji Y, Yan X, Yang F, Li F. White spot syndrome virus IE1 and WSV056 modulate the G1/S transition by binding to the host retinoblastoma protein. J Virol 2013; 87:12576-82. [PMID: 24027329 DOI: 10.1128/JVI.01551-13] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
DNA viruses often target cellular proteins to modulate host cell cycles and facilitate viral genome replication. However, whether proliferation of white spot syndrome virus (WSSV) requires regulation of the host cell cycle remains unclear. In the present study, we show that two WSSV paralogs, IE1 and WSV056, can interact with Litopenaeus vannamei retinoblastoma (Rb)-like protein (lv-RBL) through the conserved LxCxE motif. Further investigation revealed that IE1 and WSV056 could also bind to Drosophila retinoblastoma family protein 1 (RBF1) in a manner similar to how they bind to lv-RBL. Using the Drosophila RBF-E2F pathway as a model system, we demonstrated that both IE1 and WSV056 could sequester RBF1 from Drosophila E2F transcription factor 1 (E2F1) and subsequently activate E2F1 to stimulate the G1/S transition. Our findings provide the first evidence that WSSV may regulate cell cycle progression by targeting the Rb-E2F pathway.
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Abstract
Viruses are ubiquitous and extremely abundant in the marine environment. One of such marine viruses, the white spot syndrome virus (WSSV), has emerged globally as one of the most prevalent, widespread and lethal for shrimp populations. However, at present there is no treatment available to interfere with the unrestrained occurrence and spread of the disease. The recent progress in molecular biology techniques has made it possible to obtain information on the factors, mechanisms and strategies used by this virus to infect and replicate in susceptible host cells. Yet, further research is still required to fully understand the basic nature of WSSV, its exact life cycle and mode of infection. This information will expand our knowledge and may contribute to developing effective prophylactic or therapeutic measures. This review provides a state-of-the-art overview of the topic, and emphasizes the current progress and future direction for the development of WSSV control strategies.
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Affiliation(s)
- Arturo Sánchez-Paz
- Centro de Investigaciones Biologicas del Noroeste, Unidad Hermosillo, Hermosillo, Mexico.
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Borirak O, Samanphan P, Dangtip S, Kiatpathomchai W, Jitrapakdee S. Promoter motifs essential to the differential transcription of structural and non-structural genes of the white spot syndrome virus. Virus Genes 2009; 39:223-33. [DOI: 10.1007/s11262-009-0380-z] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2009] [Accepted: 06/10/2009] [Indexed: 10/20/2022]
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Escobedo-Bonilla CM, Alday-Sanz V, Wille M, Sorgeloos P, Pensaert MB, Nauwynck HJ. A review on the morphology, molecular characterization, morphogenesis and pathogenesis of white spot syndrome virus. J Fish Dis 2008; 31:1-18. [PMID: 18086030 DOI: 10.1111/j.1365-2761.2007.00877.x] [Citation(s) in RCA: 132] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/11/2023]
Abstract
Since it first appeared in 1992, white spot syndrome virus (WSSV) has become the most threatening infectious agent in shrimp aquaculture. Within a decade, this pathogen has spread to all the main shrimp farming areas and has caused enormous economic losses amounting to more than seven billion US dollars. At present, biosecurity methods used to exclude pathogens in shrimp farms include disinfecting ponds and water, preventing the entrance of animals that may carry infectious agents and stocking ponds with specific pathogen-free post-larvae. The combination of these practices increases biosecurity in shrimp farming facilities and may contribute to reduce the risk of a WSSV outbreak. Although several control methods have shown some efficacy against WSSV under experimental conditions, no therapeutic products or strategies are available to effectively control WSSV in the field. Furthermore, differences in virulence and clinical outcome of WSSV infections have been reported. The sequencing and characterization of different strains of WSSV has begun to determine aspects of its biology, virulence and pathogenesis. Knowledge on these aspects is critical for developing effective control methods. The aim of this review is to present an update of the knowledge generated so far on different aspects of WSSV organization, morphogenesis, pathology and pathogenesis.
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Affiliation(s)
- C M Escobedo-Bonilla
- Laboratory of Aquaculture and Artemia Reference Center, Faculty of Bioscience Engineering, Ghent University, Ghent, Belgium
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Abstract
White Spot Syndrome Virus (WSSV) is a virulent and widespread dsDNA virus with a wide range of hosts. Although remarkable progress has been made on virus characterization, however, its mechanism of infection is poorly understood. In this study, by analyzing the phage display library of the WSSV genome, a WSSV envelope protein VP187 (wsv209) was found to interact with shrimp integrin. VP187 possesses the RGD motif. The interaction between integrin and VP187 was confirmed with coimmunoprecipitation. These results demonstrate for the first time an interaction between the WSSV envelope protein and a cell surface molecule. Soluble integrin, integrin-specific antibody and an RGD-containing peptide were found to block the WSSV infection in vivo and in vitro. Gene silencing using a sequence-specific dsRNA targeting beta-integrin effectively inhibited the virus infection. These findings suggest that beta-integrin may function as a cellular receptor for WSSV infection.
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Affiliation(s)
- Deng-Feng Li
- Key Laboratory of Marine Biogenetic Resources, Third Institute of Oceanography, State Oceanic Administration, Xiamen 361005, P.R. China.
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Cho Y, Lee HS, Kim YJ, Kang SG, Kim SJ, Lee JH. Characterization of a dUTPase from the hyperthermophilic archaeon Thermococcus onnurineus NA1 and its application in polymerase chain reaction amplification. Mar Biotechnol (NY) 2007; 9:450-8. [PMID: 17549447 DOI: 10.1007/s10126-007-9002-8] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/14/2006] [Accepted: 02/01/2007] [Indexed: 05/15/2023]
Abstract
Genomic analysis of the hyperthermophilic archaeon Thermococcus onnurineus NA1 (TNA1) revealed the presence of a 471-bp open reading frame with 93% similarity to the dUTPase from Pyrococcus furiosus. The dUTPase-encoding gene was cloned and expressed in Escherichia coli. The purified protein hydrolyzed dUTP at about a 10-fold higher rate than dCTP. The protein behaved as a dimer in gel filtration chromatography, even though it contains five motifs that are conserved in all homotrimeric dUTPases. The dUTPase showed optimum activity at 80 degrees C and pH 8.0, and it was highly thermostable with a half-life (t (1/2)) of 170 min at 95 degrees C. The enzymatic activity of the dUTPase was largely unaffected by variations in MgCl(2), KCl, (NH(4))(2)SO(4), and Triton X-100 concentrations, although it was reduced by bovine serum albumin. Addition of the dUTPase to polymerase chain reactions (PCRs) run with TNA1 DNA polymerase significantly increased product yield, overcoming the inhibitory effect of dUTP. Further, addition of the dUTPase allowed PCR amplification of targets up to 15 kb in length using TNA1 DNA polymerase. This enzyme also improved the PCR efficiency of other archaeal family B type DNA polymerases, including Pfu and KOD.
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Affiliation(s)
- Y Cho
- Korea Ocean Research & Development Institute, Ansan, PO Box 29, Seoul 425-600, South Korea
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Zhao Z, Ke F, Gui J, Zhang Q. Characterization of an early gene encoding for dUTPase in Rana grylio virus. Virus Res 2006; 123:128-37. [PMID: 16989917 DOI: 10.1016/j.virusres.2006.08.007] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2006] [Revised: 08/18/2006] [Accepted: 08/18/2006] [Indexed: 11/22/2022]
Abstract
dUTPase (DUT) is a ubiquitous and important enzyme responsible for regulating levels of dUTP. Here, an iridovirus DUT was identified and characterized from Rana grylio virus (RGV) which is a pathogen agent in pig frog. The DUT encodes a protein of 164aa with a predicted molecular mass of 17.4 kDa, and its transcriptional initiation site was determined by 5'RACE to start from the nucleotide A at 15 nt upstream of the initiation codon ATG. Sequence comparisons and multiple alignments suggested that RGV DUT was quite similar to other identified DUTs that function as homotrimers. Phylogenetic analysis implied that DUT horizontal transfers might have occurred between the vertebrate hosts and iridoviruses. Furthermore, its temporal expression pattern during RGV infection course was characterized by RT-PCR and Western blot analysis. It begins to transcribe and translate as early as 4h postinfection (p.i.), and remains detectable at 48 h p.i. DUT-EGFP fusion protein was observed in the cytoplasm of pEGFP-N3-Dut transfected EPC cells. Immunofluorescence also confirmed DUT cytoplasm localization in RGV-infected cells. Using drug inhibition analysis by a de novo protein synthesis inhibitor (cycloheximide) and a viral DNA replication inhibitor (cytosine arabinofuranoside), RGV DUT was classified as an early (E) viral gene during the in vitro infection. Moreover, RGV DUT overexpression was shown that there was no effect on RGV replication by viral replication kinetics assay.
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Affiliation(s)
- Zhe Zhao
- 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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Marks H, Ren XY, Sandbrink H, van Hulten MCW, Vlak JM. In silico identification of putative promoter motifs of White Spot Syndrome Virus. BMC Bioinformatics 2006; 7:309. [PMID: 16784526 PMCID: PMC1550435 DOI: 10.1186/1471-2105-7-309] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2006] [Accepted: 06/19/2006] [Indexed: 11/14/2022] Open
Abstract
Background White Spot Syndrome Virus, a member of the virus family Nimaviridae, is a large dsDNA virus infecting shrimp and other crustacean species. Although limited information is available on the mode of transcription, previous data suggest that WSSV gene expression occurs in a coordinated and cascaded fashion. To search in silico for conserved promoter motifs (i) the abundance of all 4 through 8 nucleotide motifs in the upstream sequences of WSSV genes relative to the complete genome was determined, and (ii) a MEME search was performed in the upstream sequences of either early or late WSSV genes, as assigned by microarray analysis. Both methods were validated by alignments of empirically determined 5' ends of various WSSV mRNAs. Results The collective information shows that the upstream region of early WSSV genes, containing a TATA box and an initiator, is similar to Drosophila RNA polymerase II core promoter sequences, suggesting utilization of the cellular transcription machinery for generating early transcripts. The alignment of the 5' ends of known well-established late genes, including all major structural protein genes, identified a degenerate motif (ATNAC) which could be involved in WSSV late transcription. For these genes, only one contained a functional TATA box. However, almost half of the WSSV late genes, as previously assigned by microarray analysis, did contain a TATA box in their upstream region. Conclusion The data may suggest the presence of two separate classes of late WSSV genes, one exploiting the cellular RNA polymerase II system for mRNA synthesis and the other generating messengers by a new virus-induced transcription mechanism.
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Affiliation(s)
- Hendrik Marks
- Laboratory of Virology, Wageningen University, Binnenhaven 11, 6709 PD Wageningen, The Netherlands
- NCMLS/Radboud University Nijmegen, Department of Molecular Biology, Geert Grooteplein 26/28, 6525 GA, Nijmegen, The Netherlands
| | - Xin-Ying Ren
- Plant Research International, Postbus 16, 6700 AA, Wageningen, The Netherlands
| | - Hans Sandbrink
- Plant Research International, Postbus 16, 6700 AA, Wageningen, The Netherlands
| | - Mariëlle CW van Hulten
- Laboratory of Virology, Wageningen University, Binnenhaven 11, 6709 PD Wageningen, The Netherlands
- CSIRO Livestock Industries, 306 Carmody Road, St Lucia 4067, Brisbane, Australia
| | - Just M Vlak
- Laboratory of Virology, Wageningen University, Binnenhaven 11, 6709 PD Wageningen, The Netherlands
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Li L, Lin S, Yanga F. Functional identification of the non-specific nuclease from white spot syndrome virus. Virology 2005; 337:399-406. [PMID: 15913698 DOI: 10.1016/j.virol.2005.04.017] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2005] [Revised: 04/14/2005] [Accepted: 04/19/2005] [Indexed: 11/18/2022]
Abstract
The product encoded by the wsv191 gene from shrimp white spot syndrome virus (WSSV) is homologous with non-specific nucleases (NSN) of other organisms. To functionally identify the protein, the wsv191 gene was expressed in Escherichia coli as a glutathione S-transferase (GST) fusion protein with 6His-tag at C-terminal. The fusion protein (termed as rWSSV-NSN) was purified using Ni-NTA affinity chromatography under denatured conditions, renatured and characterized by three methods. The results showed that rWSSV-NSN could hydrolyze both DNA and RNA. 5'-RACE result revealed that the transcription initiation site of the wsv191 gene was located at nucleotide residue G of the predicted ATG triplet. Therefore, we concluded that the next ATG should be the genuine translation initiation codon of the wsv191 gene. Western blot analysis revealed that the molecular mass of natural WSSV-NSN was 37 kDa.
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Affiliation(s)
- Li Li
- Key Laboratory of Marine Biogenetic Resources, Third Institute of Oceanography, SOA, 178 Daxue Road, Xiamen 361005, P.R. China
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