Iridovirus poses a substantial threat to global aquaculture due to its high mortality rate;however,the molecular mechanisms underpinning its pathogenesis are not well elucidated.Here,a multi-omics approach was applied...Iridovirus poses a substantial threat to global aquaculture due to its high mortality rate;however,the molecular mechanisms underpinning its pathogenesis are not well elucidated.Here,a multi-omics approach was applied to groupers infected with Singapore grouper iridovirus(SGIV),focusing on the roles of key metabolites.Results showed that SGIV induced obvious histopathological damage and changes in metabolic enzymes within the liver.Furthermore,SGIV significantly reduced the contents of lipid droplets,triglycerides,cholesterol,and lipoproteins.Metabolomic analysis indicated that the altered metabolites were enriched in 19 pathways,with a notable down-regulation of lipid metabolites such as glycerophosphates and alpha-linolenic acid(ALA),consistent with disturbed lipid homeostasis in the liver.Integration of transcriptomic and metabolomic data revealed that the top enriched pathways were related to cell growth and death and nucleotide,carbohydrate,amino acid,and lipid metabolism,supporting the conclusion that SGIV infection induced liver metabolic reprogramming.Further integrative transcriptomic and proteomic analysis indicated that SGIV infection activated crucial molecular events in a phagosome-immune depression-metabolism dysregulation-necrosis signaling cascade.Of note,integrative multi-omics analysis demonstrated the consumption of ALA and linoleic acid(LA)metabolites,and the accumulation of L-glutamic acid(GA),accompanied by alterations in immune,inflammation,and cell death-related genes.Further experimental data showed that ALA,but not GA,suppressed SGIV replication by activating antioxidant and anti-inflammatory responses in the host.Collectively,these findings provide a comprehensive resource for understanding host response dynamics during fish iridovirus infection and highlight the antiviral potential of ALA in the prevention and treatment of iridoviral diseases.展开更多
A rapid and sensitive PCR-based method for the detection of the large yellow croaker iridovirus (LYCIV) is described, which involves the amplification of a 295 bp fragment of the LYCIV ATPase gene from DNA isolated fr...A rapid and sensitive PCR-based method for the detection of the large yellow croaker iridovirus (LYCIV) is described, which involves the amplification of a 295 bp fragment of the LYCIV ATPase gene from DNA isolated from naturally infected fish spleen. Sequencing of LYCIV ATPase gene fragment showed it shared 100% nucleotide sequence homology with the corresponding region of the ATPase gene of red sea bream iridovirus (RSIV) and sea bass iridovirus (SBIV), suggesting that LYCIV was homologous with RSIV and SBIV at least in part of the gemone. The specificity and sensitivity of the PCR procedure were tested on the iridovirus-infected fishes, the expected fragment was detected from spleen DNA samples of infected fishes, whereas no fragments were amplified from healthy fish spleen DNA, white spot syndrome baculoviruses (WSBV) DNA and pseudorabies virus (PRV) DNA. Detection limit of this method was 10(-7) ng positive plasmid DNA containing target sequence, equal to about 100 virions. In the infected experiment, first positive detection (1/4) appeared at Day 3 post-infection, all fish (4/4) tested positive at Day 7, however obvious symptoms were observed at Day 8, so LYCIV infection could be detected prior to the appearance of obvious symptoms. These results indicate that this PCR method could be used for early, rapid and specific detection of LYCIV infection.展开更多
Turbot(Scophthalmus maximus L.) reddish body iridovirus(TRBIV) was propagated in turbot fin cells(TF cells) and inactivated as the TRBIV vaccine with its protection efficiency evaluated in this study.TF cells were cul...Turbot(Scophthalmus maximus L.) reddish body iridovirus(TRBIV) was propagated in turbot fin cells(TF cells) and inactivated as the TRBIV vaccine with its protection efficiency evaluated in this study.TF cells were cultured in 10% bovine calf serum(BCS)-containing MEM medium(pH7.0) at 22℃,in which TRBIV propagated to a titer as high as 105.6 TCID50 mL-1.The TRBIV was inactivated with 0.1% formalin and formulated with 0.5% aluminum hydroxide.The inactivated vaccine caused neither cytopathogenic effect(CPE) on TF cells nor pathogenic effect on turbots.After being administered with the vaccine twice via muscle injection,the turbot developed high-tittered TRBIV neutralizing antibodies in a dose-dependent manner.The vaccine protected the turbot from dying with an immunoprotection rate of 83.3% as was determined via subcutaneous vaccination in the laboratory and 90.5% via bath vaccination in turbot farms,respectively.The inactivated vaccine was very immunogenic,efficiently preventing tur-bot from death.It holds the potential of being applied in aquaculture.展开更多
Coagulation test, in principle, is an immunodiagnostics technique, in which immunoglobuline G of antibody is bound to protein A from Staphylococcus aureus. The aim of study is to develop a rapid test kit for detecting...Coagulation test, in principle, is an immunodiagnostics technique, in which immunoglobuline G of antibody is bound to protein A from Staphylococcus aureus. The aim of study is to develop a rapid test kit for detecting iridovirus infection in fish. Method was summarized as follows： （1） vaccine of iridovirus was injected to rabbit four times with a dosage as 0.5 mL, 1 mL, 2mL, 3 mL each week. Serum was collected at the fifth week as a coagglutination test kit; （2） through the positif polymerase chain reaction （PCR） test, the kidney and spleen sample infected with iridovirus are homogenized by using the phosphate buffered saline （PBS） solution of pH 7.2 with ratio 1：2 （WN）; （3） the supernatant material is collected after centrifugation at 8,000 rpm for 15 min; （4） filtrate/supernatant from sample was dropped on a slide an added with coagglutination test kit with the same volume （l：l）; （5） the agglutination observation is done after the 30, 60 and 90 min incubate at room temperature. The coagglutination test gave positive result in 25% of the test samples.展开更多
Iridovirus infection often causes death and considerable economic losses in the aquaculture industry. This research applies the co-agglutination method that is fast, cheap and accurate in confirming the diagnosis of t...Iridovirus infection often causes death and considerable economic losses in the aquaculture industry. This research applies the co-agglutination method that is fast, cheap and accurate in confirming the diagnosis of the cause of an outbreak of illness caused by iridovirus in the field, so that remedial action can be taken quickly and appropriately to minimize the impact of wider losses. Samples were taken from the grouper and pomfret star farms that are experiencing outbreaks of infectious diseases in the months from May to August 2015, Tanjungpinang, Indonesia. The sick and allegedly attacked by iridovirus samples showed abnormal swimming clinical symptoms, weakness and the swollen spleen. The swollen spleen of sick fish created suspension in phosphate buffered saline （PBS） with pH 7.2, and then centrifuged at 8,000 rpm for I0 rain. The supernatant after centrifuge was used as the test sample. On a clean object glass, 50 μL of the supematant was treated with 50 μL kit co-agglutination pre-prepared. The positive results were shown by the agglutination reaction after 10-15 rain, while as a negative control, PBS was reacted with co-agglutination kit that looked homogeneous （no agglutination）. It was showed that the grouper （Epinepkelus sp.） on four farms and pomfret star （Thracinotus blochii） on one farm that experienced an outbreak of infectious disease in Tanjungpinang showed positively infected iridovirus. The same positive iridovirus result was also demonstrated by examination using polymerase chain reaction （PCR） at 570 bp. So, the causative agent of plague on grouper and pomfret star was iridovirus. In addition, the co-agglutination test based on serology is more quick, cheap and accurate.展开更多
Iridoviruses are DNA virus and have caused huge economic losses in the aquaculture industry.The aim of this study was to establish a colorimetric loop-mediated isothermal amplification(LAMP)protocol for the on-site de...Iridoviruses are DNA virus and have caused huge economic losses in the aquaculture industry.The aim of this study was to establish a colorimetric loop-mediated isothermal amplification(LAMP)protocol for the on-site detection of Singapore grouper iridovirus(SGIV).The SGIV-VP61 gene was chosen as the target gene to develop a colorimetric LAMP assay.The optimized condition of the colorimetric LAMP assay was incubation at 63℃ for 1 h.Samples infected with SGIV could be detected with the color change from yellow into pink.The sensitivity of the developed assay is 5.66 copies/μL of the viral DNA template.This sensitivity was about 1000 times higher than that of conventional PCR while it was slightly lower than the one-step semi-nested PCR assay.A total of 60 DNA samples extracted from the fin tissue of the SGIV-infected Asian seabass were examined for SGIV by colorimetric LAMP,semi-nested PCR and conventional PCR.The results of the colorimetric LAMP assay showed 94.87%agreement with the semi-nested PCR.In addition,the DNA extraction method using NaOH showed a better performance in the colorimetric LAMP assay.Taken together,the colorimetric LAMP established was a sensitive,rapid and specific method for the detection of SGIV.SGIV was not detected in samples randomly taken from a genetically improved line of the Asian seabass.However,some seabass obtained from the local markets were found to contain SGIV.Thus,the LAMP assay has the potential application in the diagnosis of iridovirus diseases in the aquaculture industry.展开更多
Chilo iridescent virus (CIV) is the type species for genus Iridovirus, and belongs to the family Iridoviridae. Since the discovery of CIV in 1966, many attempts were made to elucidate the viral genome structure. The v...Chilo iridescent virus (CIV) is the type species for genus Iridovirus, and belongs to the family Iridoviridae. Since the discovery of CIV in 1966, many attempts were made to elucidate the viral genome structure. The virions contain a single linear ds DNA molecule that is circularly permuted and terminally redundant. The genome of CIV has been entirely sequenced. The CIV virion consists of an unusual three-layer structure containing an outer proteinaceous capsid, an intermediate lipid membrane, and a core DNA-protein complex containing the genome. CIV has a broad host spectrum and has, in general, a limited mortality effect on its hosts. Up to now there have been several studies about CIV describing its structure, ecology, and molecular biology. In this review study we present all these studies together to describe the CIV.展开更多
Over the last 30 years,aquaculture has become the fastest growing form of agriculture production in the world,but its development has been hampered by a diverse range of pathogenic viruses.During the last decade,a lar...Over the last 30 years,aquaculture has become the fastest growing form of agriculture production in the world,but its development has been hampered by a diverse range of pathogenic viruses.During the last decade,a large number of viruses from aquatic animals have been identified,and more than 100 viral genomes have been sequenced and genetically characterized.These advances are leading to better understanding about antiviral mechanisms and the types of interaction occurring between aquatic viruses and their hosts.Here,based on our research experience of more than 20 years,we review the wealth of genetic and genomic information from studies on a diverse range of aquatic viruses,including iridoviruses,herpesviruses,reoviruses,and rhabdoviruses,and outline some major advances in our understanding of virus–host interactions in animals used in aquaculture.展开更多
To identify the abnormal characteristics of the oplegnathus punctatus is great importance to the detection of iridovirus disease in the breeding environment.In this paper,an advanced neural network model to identify t...To identify the abnormal characteristics of the oplegnathus punctatus is great importance to the detection of iridovirus disease in the breeding environment.In this paper,an advanced neural network model to identify the characteristics of the oplegnathus puncta-tus and predict its different periods of suffering from iridovirus disease is proposed based on the establishment of a data set.First of all,a standard format data set of oplegnathus punctatus and an abnormal format date set are established in order to verify the effective-ness of the method in this paper.And then,the feature extraction fusion method is used for preprocessing in terms of the abnormal format data set,which combines the edge fea-tures extracted by the improved multi-template Sobel operator and the color features extracted by the HSV model.Finally,an improved VGG-GoogleNet network recognition model comes into being through the fusion and improvement of the VGG and GoogleNet neural network structure.The experiments results show that the prediction accuracy rate for oplegnathus punctatus suffering from iridovirus disease in the the abnormal format data set and the standard format data set are improved,which reach 98.55%and 69.18%.展开更多
基金supported by the National Natural Science Foundation of China(31930115,32173007)China Agriculture Research System of MOF and MARA(CARS-47-G16)Basic and Applied Basic Research Foundation of Guangdong Province(2022A1515010595)。
文摘Iridovirus poses a substantial threat to global aquaculture due to its high mortality rate;however,the molecular mechanisms underpinning its pathogenesis are not well elucidated.Here,a multi-omics approach was applied to groupers infected with Singapore grouper iridovirus(SGIV),focusing on the roles of key metabolites.Results showed that SGIV induced obvious histopathological damage and changes in metabolic enzymes within the liver.Furthermore,SGIV significantly reduced the contents of lipid droplets,triglycerides,cholesterol,and lipoproteins.Metabolomic analysis indicated that the altered metabolites were enriched in 19 pathways,with a notable down-regulation of lipid metabolites such as glycerophosphates and alpha-linolenic acid(ALA),consistent with disturbed lipid homeostasis in the liver.Integration of transcriptomic and metabolomic data revealed that the top enriched pathways were related to cell growth and death and nucleotide,carbohydrate,amino acid,and lipid metabolism,supporting the conclusion that SGIV infection induced liver metabolic reprogramming.Further integrative transcriptomic and proteomic analysis indicated that SGIV infection activated crucial molecular events in a phagosome-immune depression-metabolism dysregulation-necrosis signaling cascade.Of note,integrative multi-omics analysis demonstrated the consumption of ALA and linoleic acid(LA)metabolites,and the accumulation of L-glutamic acid(GA),accompanied by alterations in immune,inflammation,and cell death-related genes.Further experimental data showed that ALA,but not GA,suppressed SGIV replication by activating antioxidant and anti-inflammatory responses in the host.Collectively,these findings provide a comprehensive resource for understanding host response dynamics during fish iridovirus infection and highlight the antiviral potential of ALA in the prevention and treatment of iridoviral diseases.
文摘A rapid and sensitive PCR-based method for the detection of the large yellow croaker iridovirus (LYCIV) is described, which involves the amplification of a 295 bp fragment of the LYCIV ATPase gene from DNA isolated from naturally infected fish spleen. Sequencing of LYCIV ATPase gene fragment showed it shared 100% nucleotide sequence homology with the corresponding region of the ATPase gene of red sea bream iridovirus (RSIV) and sea bass iridovirus (SBIV), suggesting that LYCIV was homologous with RSIV and SBIV at least in part of the gemone. The specificity and sensitivity of the PCR procedure were tested on the iridovirus-infected fishes, the expected fragment was detected from spleen DNA samples of infected fishes, whereas no fragments were amplified from healthy fish spleen DNA, white spot syndrome baculoviruses (WSBV) DNA and pseudorabies virus (PRV) DNA. Detection limit of this method was 10(-7) ng positive plasmid DNA containing target sequence, equal to about 100 virions. In the infected experiment, first positive detection (1/4) appeared at Day 3 post-infection, all fish (4/4) tested positive at Day 7, however obvious symptoms were observed at Day 8, so LYCIV infection could be detected prior to the appearance of obvious symptoms. These results indicate that this PCR method could be used for early, rapid and specific detection of LYCIV infection.
基金supported by the National High Technology Research and Development Program of China(863 Program)(2006AA10A401)
文摘Turbot(Scophthalmus maximus L.) reddish body iridovirus(TRBIV) was propagated in turbot fin cells(TF cells) and inactivated as the TRBIV vaccine with its protection efficiency evaluated in this study.TF cells were cultured in 10% bovine calf serum(BCS)-containing MEM medium(pH7.0) at 22℃,in which TRBIV propagated to a titer as high as 105.6 TCID50 mL-1.The TRBIV was inactivated with 0.1% formalin and formulated with 0.5% aluminum hydroxide.The inactivated vaccine caused neither cytopathogenic effect(CPE) on TF cells nor pathogenic effect on turbots.After being administered with the vaccine twice via muscle injection,the turbot developed high-tittered TRBIV neutralizing antibodies in a dose-dependent manner.The vaccine protected the turbot from dying with an immunoprotection rate of 83.3% as was determined via subcutaneous vaccination in the laboratory and 90.5% via bath vaccination in turbot farms,respectively.The inactivated vaccine was very immunogenic,efficiently preventing tur-bot from death.It holds the potential of being applied in aquaculture.
文摘Coagulation test, in principle, is an immunodiagnostics technique, in which immunoglobuline G of antibody is bound to protein A from Staphylococcus aureus. The aim of study is to develop a rapid test kit for detecting iridovirus infection in fish. Method was summarized as follows： （1） vaccine of iridovirus was injected to rabbit four times with a dosage as 0.5 mL, 1 mL, 2mL, 3 mL each week. Serum was collected at the fifth week as a coagglutination test kit; （2） through the positif polymerase chain reaction （PCR） test, the kidney and spleen sample infected with iridovirus are homogenized by using the phosphate buffered saline （PBS） solution of pH 7.2 with ratio 1：2 （WN）; （3） the supernatant material is collected after centrifugation at 8,000 rpm for 15 min; （4） filtrate/supernatant from sample was dropped on a slide an added with coagglutination test kit with the same volume （l：l）; （5） the agglutination observation is done after the 30, 60 and 90 min incubate at room temperature. The coagglutination test gave positive result in 25% of the test samples.
文摘Iridovirus infection often causes death and considerable economic losses in the aquaculture industry. This research applies the co-agglutination method that is fast, cheap and accurate in confirming the diagnosis of the cause of an outbreak of illness caused by iridovirus in the field, so that remedial action can be taken quickly and appropriately to minimize the impact of wider losses. Samples were taken from the grouper and pomfret star farms that are experiencing outbreaks of infectious diseases in the months from May to August 2015, Tanjungpinang, Indonesia. The sick and allegedly attacked by iridovirus samples showed abnormal swimming clinical symptoms, weakness and the swollen spleen. The swollen spleen of sick fish created suspension in phosphate buffered saline （PBS） with pH 7.2, and then centrifuged at 8,000 rpm for I0 rain. The supernatant after centrifuge was used as the test sample. On a clean object glass, 50 μL of the supematant was treated with 50 μL kit co-agglutination pre-prepared. The positive results were shown by the agglutination reaction after 10-15 rain, while as a negative control, PBS was reacted with co-agglutination kit that looked homogeneous （no agglutination）. It was showed that the grouper （Epinepkelus sp.） on four farms and pomfret star （Thracinotus blochii） on one farm that experienced an outbreak of infectious disease in Tanjungpinang showed positively infected iridovirus. The same positive iridovirus result was also demonstrated by examination using polymerase chain reaction （PCR） at 570 bp. So, the causative agent of plague on grouper and pomfret star was iridovirus. In addition, the co-agglutination test based on serology is more quick, cheap and accurate.
基金This study was supported by the National Natural Science Foundation of China(41806161)the internal funds of Temasek Life Sciences Lab,Singapore.
文摘Iridoviruses are DNA virus and have caused huge economic losses in the aquaculture industry.The aim of this study was to establish a colorimetric loop-mediated isothermal amplification(LAMP)protocol for the on-site detection of Singapore grouper iridovirus(SGIV).The SGIV-VP61 gene was chosen as the target gene to develop a colorimetric LAMP assay.The optimized condition of the colorimetric LAMP assay was incubation at 63℃ for 1 h.Samples infected with SGIV could be detected with the color change from yellow into pink.The sensitivity of the developed assay is 5.66 copies/μL of the viral DNA template.This sensitivity was about 1000 times higher than that of conventional PCR while it was slightly lower than the one-step semi-nested PCR assay.A total of 60 DNA samples extracted from the fin tissue of the SGIV-infected Asian seabass were examined for SGIV by colorimetric LAMP,semi-nested PCR and conventional PCR.The results of the colorimetric LAMP assay showed 94.87%agreement with the semi-nested PCR.In addition,the DNA extraction method using NaOH showed a better performance in the colorimetric LAMP assay.Taken together,the colorimetric LAMP established was a sensitive,rapid and specific method for the detection of SGIV.SGIV was not detected in samples randomly taken from a genetically improved line of the Asian seabass.However,some seabass obtained from the local markets were found to contain SGIV.Thus,the LAMP assay has the potential application in the diagnosis of iridovirus diseases in the aquaculture industry.
文摘Chilo iridescent virus (CIV) is the type species for genus Iridovirus, and belongs to the family Iridoviridae. Since the discovery of CIV in 1966, many attempts were made to elucidate the viral genome structure. The virions contain a single linear ds DNA molecule that is circularly permuted and terminally redundant. The genome of CIV has been entirely sequenced. The CIV virion consists of an unusual three-layer structure containing an outer proteinaceous capsid, an intermediate lipid membrane, and a core DNA-protein complex containing the genome. CIV has a broad host spectrum and has, in general, a limited mortality effect on its hosts. Up to now there have been several studies about CIV describing its structure, ecology, and molecular biology. In this review study we present all these studies together to describe the CIV.
基金supported by grants from the National Natural Science Foundation of China(31430091)the National Key Basic Research Program(2010CB126303)the Project of State Key Laboratory of Freshwater Ecology and Biotechnology(2011FBZ12)
文摘Over the last 30 years,aquaculture has become the fastest growing form of agriculture production in the world,but its development has been hampered by a diverse range of pathogenic viruses.During the last decade,a large number of viruses from aquatic animals have been identified,and more than 100 viral genomes have been sequenced and genetically characterized.These advances are leading to better understanding about antiviral mechanisms and the types of interaction occurring between aquatic viruses and their hosts.Here,based on our research experience of more than 20 years,we review the wealth of genetic and genomic information from studies on a diverse range of aquatic viruses,including iridoviruses,herpesviruses,reoviruses,and rhabdoviruses,and outline some major advances in our understanding of virus–host interactions in animals used in aquaculture.
基金The work of this paper is jointly supported by the National Natural Science Foundation of China (U1706220,61472172)the Yantai Key R&D Project (2017ZH057,2018ZDCX003,2019XDHZ084).
文摘To identify the abnormal characteristics of the oplegnathus punctatus is great importance to the detection of iridovirus disease in the breeding environment.In this paper,an advanced neural network model to identify the characteristics of the oplegnathus puncta-tus and predict its different periods of suffering from iridovirus disease is proposed based on the establishment of a data set.First of all,a standard format data set of oplegnathus punctatus and an abnormal format date set are established in order to verify the effective-ness of the method in this paper.And then,the feature extraction fusion method is used for preprocessing in terms of the abnormal format data set,which combines the edge fea-tures extracted by the improved multi-template Sobel operator and the color features extracted by the HSV model.Finally,an improved VGG-GoogleNet network recognition model comes into being through the fusion and improvement of the VGG and GoogleNet neural network structure.The experiments results show that the prediction accuracy rate for oplegnathus punctatus suffering from iridovirus disease in the the abnormal format data set and the standard format data set are improved,which reach 98.55%and 69.18%.
