The Experts below are selected from a list of 279 Experts worldwide ranked by ideXlab platform
John P. Burand - One of the best experts on this subject based on the ideXlab platform.
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Analysis of the Genome of the Sexually Transmitted Insect Virus Helicoverpa zea NudiVirus 2
Viruses, 2012Co-Authors: John P. Burand, Gerald F. Kutish, Zhiqiang Lu, E. R. Tulman, Claudio L Afonso, Daniel L. RockAbstract:The sexually transmitted Insect Virus Helicoverpa zea nudiVirus 2 (HzNV-2) was determined to have a circular double-stranded DNA genome of 231,621 bp coding for an estimated 113 open reading frames (ORFs). HzNV-2 is most closely related to the nudiViruses, a sister group of the Insect baculoViruses. Several putative ORFs that share homology with the baculoVirus core genes were identified in the viral genome. However, HzNV-2 lacks several key genetic features of baculoViruses including the late transcriptional regulation factor, LEF-1 and the palindromic hrs, which serve as origins of replication. The HzNV-2 genome was found to code for three ORFs that had significant sequence homology to cellular genes which are not generally found in viral genomes. These included a presumed juvenile hormone esterase gene, a gene coding for a putative zinc-dependent matrix metalloprotease, and a major facilitator superfamily protein gene; all of which are believed to play a role in the cellular proliferation and the tissue hypertrophy observed in the malformation of reproductive organs observed in HzNV-2 infected corn earworm moths, Helicoverpa zea.
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The sexually transmitted Insect Virus, Hz-2V
Virologica Sinica, 2009Co-Authors: John P. BurandAbstract:Hz-2V is one of only a very few sexually transmitted Viruses currently known in Insects. Replication of this Insect pathogenic Virus results in sterility of infected moths rather than mortality. The sterility of the infected host is a consequence of Virus directed malformation of adult reproductive tissues, which in females results in cellular proliferation and hypertrophy of these tissues. Virus replication has additional ramifications in infected females. Infected females produce more mating pheromones and attract more mates than healthy females, ultimately facilitating Virus transmission and enhancing viral fitness. The molecular mechanisms used by the Virus to manipulate the host to enhance its fitness are yet to be determined. Unraveling the underlying principles of these mechanisms promises to enhance our understanding of Insect reproductive physiology, as well as provide molecular tools for use in novel approaches in sterile Insect control programs.
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Location, Nucleotide Sequence, and Regulation of the P51 Late Gene of the Hz-1 Insect Virus: Identification of a Putative Late Regulatory Element
Virus Genes, 2001Co-Authors: Mary C. Guttieri, John P. BurandAbstract:An Hz-1 Insect Virus (Hz-1V) late gene encoding, a predicted polypeptide of 51 kDa was isolated from a cDNA library and mapped to the Hin dIII-J region (40–44.6 map units) of the viral genome. The p51 gene was characterized by DNA sequence, Northern blot, and primer extension analyses. The 1,152 bp open reading frame (ORF) is transcribed as a 1.8 kb RNA between 8 and 18 h post-infection (hpi) with maximum expression at 12 hpi. Homology was not detected between the nucleotide sequence upstream of the p51 ORF and the baculoVirus conserved late promoter element NTAAG. Primer extension analysis detected one major late transcription initiation site at −205 nucleotides relative to the start of the p51 ORF and seven minor late initiation sites at positions upstream of this primary site. Comparison of the upstream regulatory regions of the p51 gene and the Hz-1V p34 late gene revealed a region of significant homology comprised of the 9 bp sequence TTATAGTAT. The primary p51 transcription initiation site and all p34 transcription initiation sites were mapped to different nucleotides within this nonanucleotide sequence. This 9 bp motif was not observed in the ORFs of these genes, and no significant homology was detected between this motif and the 5′ regulatory regions of any other characterized genes. The results of our study suggest that this conserved sequence may serve an important role in the regulation of Hz-1V late genes.
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Replication of a Gonad-Specific Insect Virus in TN-368 Cells in Culture
Journal of Invertebrate Pathology, 1997Co-Authors: John P. BurandAbstract:A newly discovered, nonoccluded, Insect Virus, known as gonad-specific Virus (GSV) was found to replicate in Trichoplusia ni (TN-368) tissue culture cells. Light-microscope observations indicated that 90% of the infected cells showed cytopathic effects by 2 days postinoculation. Electron-microscopic observations revealed the productive replication of this nonoccluded Virus with enveloped Virus particles clearly visible in the nucleus of infected cells. These particles had approximately the same size and shape reported for GSV recovered from the in vivo host, Helicoverpa zea (corn earworm). Southern blot analysis indicated that the EcoRI restriction enzyme profiles of viral DNA from GSV-infected TN-368 were nearly identical to that of viral DNA from Insects. Inoculation of healthy female, H. zea adults with cell-culture-derived Virus yielded progeny moths with the same symptoms as Insects inoculated with GSV propagated in vivo. These studies clearly demonstrate the ability of GSV to replicate in TN-368 cells in culture.
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Nucleotide Sequence, Temporal Expression, and Transcriptional Mapping of the p34 Late Gene of the Hz-1 Insect Virus
Virology, 1996Co-Authors: Mary C. Guttieri, John P. BurandAbstract:Abstract A late gene of the Hz-1 Insect Virus (Hz-1V) encoding a predicted polypeptide of 34 kilodaltons (kDa) was isolated from a cDNA library and mapped to theHindIII-T region (50.3 to 52.4 map units) of the viral genome. The p34 gene was characterized by DNA sequence, Northern blot, and primer extension analyses. The 765-bp open reading frame (ORF) is transcribed in the clockwise direction as a 1.2-kb RNA. Primer extension analysis detected two late transcription initiation sites at −16 and −17 nt relative to the start of the p34 ORF. Transcription initiation was observed between 4 and 18 hr postinfection (hr p.i.) with maximum expression at 12 hr p.i. No nucleotide sequence homology was detected between the regulatory region of the p34 gene and the baculoVirus conserved late promoter motif NTAAG. This observation was substantiated by results obtained from an investigation of Hz-1V late gene expression using a transient expression assay system which suggested that Hz-1V late gene promoters do not resemble the baculoVirus late promoter motif. This is the first molecular analysis of Hz-1V late gene expression and offers a basis by which to compare Hz-1V to other Insect Viruses.
Bryony C. Bonning - One of the best experts on this subject based on the ideXlab platform.
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aphis glycines Virus 2 a novel Insect Virus with a unique genome structure
Viruses, 2016Co-Authors: Diveena Vijayendran, Yuting Chen, Bryony C. BonningAbstract:The invasive soybean aphid, Aphis glycines, is a major pest in soybeans, resulting in substantial economic loss. We analyzed the A. glycines transcriptome to identify sequences derived from Viruses of A. glycines. We identified sequences derived from a novel Virus named Aphis glycines Virus 2 (ApGlV2). The assembled Virus genome sequence was confirmed by reverse transcription polymerase chain reaction (RT-PCR) and Sanger sequencing, conserved domains were characterized, and distribution, and transmission examined. This Virus has a positive sense, single-stranded RNA genome of ~4850 nt that encodes three proteins. The RNA-dependent RNA polymerase (RdRp) of ApGlV2 is a permuted RdRp similar to those of some tetraViruses, while the capsid protein is structurally similar to the capsid proteins of plant sobemoViruses. ApGlV2 also encodes a larger minor capsid protein, which is translated by a readthrough mechanism. ApGlV2 appears to be widespread in A. glycines populations and to persistently infect aphids with a 100% vertical transmission rate. ApGlV2 is susceptible to the antiviral RNA interference (RNAi) pathway. This Virus, with its unique genome structure with both plant- and Insect-Virus characteristics, is of particular interest from an evolutionary standpoint.
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Next generation sequencing technologies for Insect Virus discovery.
Viruses, 2011Co-Authors: Sijun Liu, Diveena Vijayendran, Bryony C. BonningAbstract:Insects are commonly infected with multiple Viruses including those that cause sublethal, asymptomatic, and latent infections. Traditional methods for Virus isolation typically lack the sensitivity required for detection of such Viruses that are present at low abundance. In this respect, next generation sequencing technologies have revolutionized methods for the discovery and identification of new Viruses from Insects. Here we review both traditional and modern methods for Virus discovery, and outline analysis of transcriptome and small RNA data for identification of viral sequences. We will introduce methods for de novo assembly of viral sequences, identification of potential viral sequences from BLAST data, and bioinformatics for generating full-length or near full-length viral genome sequences. We will also discuss implications of the ubiquity of Viruses in Insects and in Insect cell lines. All of the methods described in this article can also apply to the discovery of Viruses in other organisms.
Daniel L. Rock - One of the best experts on this subject based on the ideXlab platform.
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Analysis of the Genome of the Sexually Transmitted Insect Virus Helicoverpa zea NudiVirus 2
Viruses, 2012Co-Authors: John P. Burand, Gerald F. Kutish, Zhiqiang Lu, E. R. Tulman, Claudio L Afonso, Daniel L. RockAbstract:The sexually transmitted Insect Virus Helicoverpa zea nudiVirus 2 (HzNV-2) was determined to have a circular double-stranded DNA genome of 231,621 bp coding for an estimated 113 open reading frames (ORFs). HzNV-2 is most closely related to the nudiViruses, a sister group of the Insect baculoViruses. Several putative ORFs that share homology with the baculoVirus core genes were identified in the viral genome. However, HzNV-2 lacks several key genetic features of baculoViruses including the late transcriptional regulation factor, LEF-1 and the palindromic hrs, which serve as origins of replication. The HzNV-2 genome was found to code for three ORFs that had significant sequence homology to cellular genes which are not generally found in viral genomes. These included a presumed juvenile hormone esterase gene, a gene coding for a putative zinc-dependent matrix metalloprotease, and a major facilitator superfamily protein gene; all of which are believed to play a role in the cellular proliferation and the tissue hypertrophy observed in the malformation of reproductive organs observed in HzNV-2 infected corn earworm moths, Helicoverpa zea.
Peng Chen - One of the best experts on this subject based on the ideXlab platform.
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construction of a one vector multiplex crispr cas9 editing system to inhibit nucleopolyhedroVirus replication in silkworms
Virologica Sinica, 2019Co-Authors: Zhan-qi Dong, Qi Qin, Liang Huang, Xinling Zhang, Ting Tian, Peng Chen, Min-hui PanAbstract:Recently the developed single guide (sg)RNA-guided clustered regularly interspaced short palindromic repeats/associated protein 9 nuclease (CRISPR/Cas9) technology has opened a new avenue for antiviral therapy. The CRISPR/Cas9 system uniquely allows targeting of multiple genome sites simultaneously. However, there are relatively few applications of CRISPR/Cas9 multigene editing to target Insect Viruses. To address the need for sustained delivery of a multiplex CRISPR/Cas9-based genome-editing vehicle against Insect Viruses, we developed a one-vector (pSL1180-Cas9-U6-sgRNA) system that expresses multiple sgRNA and Cas9 protein to excise Bombyx mori nucleopolyhedroVirus (BmNPV) in Insect cells. We screened the immediate-early-1 gene (ie-1), the major envelope glycoprotein gene (gp64), and the late expression factor gene (lef-11), and identified multiple sgRNA editing sites through flow cytometry and viral DNA replication analysis. In addition, we constructed a multiplex editing vector (PSL1180-Cas9-sgIE1-sgLEF11-sgGP64, sgMultiple) to efficiently regulate multiplex gene-editing and inhibit BmNPV replication after viral infection. This is the first report of the application of a multiplex CRISPR/Cas9 system to inhibit Insect Virus replication. This multiplex system can significantly enhance the potential of CRISPR/Cas9-based multiplex genome engineering in Insect Virus.
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Construction of a One-Vector Multiplex CRISPR/Cas9 Editing System to Inhibit NucleopolyhedroVirus Replication in Silkworms.
Virologica Sinica, 2019Co-Authors: Zhan-qi Dong, Qi Qin, Liang Huang, Xinling Zhang, Ting Tian, Peng Chen, Min-hui PanAbstract:Recently the developed single guide (sg)RNA-guided clustered regularly interspaced short palindromic repeats/associated protein 9 nuclease (CRISPR/Cas9) technology has opened a new avenue for antiviral therapy. The CRISPR/Cas9 system uniquely allows targeting of multiple genome sites simultaneously. However, there are relatively few applications of CRISPR/Cas9 multigene editing to target Insect Viruses. To address the need for sustained delivery of a multiplex CRISPR/Cas9-based genome-editing vehicle against Insect Viruses, we developed a one-vector (pSL1180-Cas9-U6-sgRNA) system that expresses multiple sgRNA and Cas9 protein to excise Bombyx mori nucleopolyhedroVirus (BmNPV) in Insect cells. We screened the immediate-early-1 gene (ie-1), the major envelope glycoprotein gene (gp64), and the late expression factor gene (lef-11), and identified multiple sgRNA editing sites through flow cytometry and viral DNA replication analysis. In addition, we constructed a multiplex editing vector (PSL1180-Cas9-sgIE1-sgLEF11-sgGP64, sgMultiple) to efficiently regulate multiplex gene-editing and inhibit BmNPV replication after viral infection. This is the first report of the application of a multiplex CRISPR/Cas9 system to inhibit Insect Virus replication. This multiplex system can significantly enhance the potential of CRISPR/Cas9-based multiplex genome engineering in Insect Virus.
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Virome comparisons in wild-diseased and healthy captive giant pandas.
Microbiome, 2017Co-Authors: Wen Zhang, Shixing Yang, Tongling Shan, Wang Li, Yan Wang, Peng Chen, Xiaochun WangAbstract:The giant panda (Ailuropoda melanoleuca) is a vulnerable mammal herbivore living wild in central China. Viral infections have become a potential threat to the health of these endangered animals, but limited information related to these infections is available. Using a viral metagenomic approach, we surveyed Viruses in the feces, nasopharyngeal secretions, blood, and different tissues from a wild giant panda that died from an unknown disease, a healthy wild giant panda, and 46 healthy captive animals. The previously uncharacterized complete or near complete genomes of four Viruses from three genera in Papillomaviridae family, six Viruses in a proposed new Picornaviridae genus (AimelVirus), two unclassified Viruses related to posaViruses in Picornavirales order, 19 anelloViruses in four different clades of Anelloviridae family, four putative circoViruses, and 15 Viruses belonging to the recently described Genomoviridae family were sequenced. Reflecting the diet of giant pandas, numerous Insect Virus sequences related to the families Iflaviridae, Dicistroviridae, Iridoviridae, Baculoviridae, Polydnaviridae, and subfamily Densovirinae and plant Viruses sequences related to the families Tombusviridae, Partitiviridae, Secoviridae, Geminiviridae, Luteoviridae, Virgaviridae, and Rhabdoviridae; genus UmbraVirus, Alphaflexiviridae, and Phycodnaviridae were also detected in fecal samples. A small number of Insect Virus sequences were also detected in the nasopharyngeal secretions of healthy giant pandas and lung tissues from the dead wild giant panda. Although the viral families present in the sick giant panda were also detected in the healthy ones, a higher proportion of papillomaViruses, picornaViruses, and anelloViruses reads were detected in the diseased panda. This viral survey increases our understanding of eukaryotic Viruses in giant pandas and provides a baseline for comparison to Viruses detected in future infectious disease outbreaks. The similar viral families detected in sick and healthy giant pandas indicate that these Viruses result in commensal infections in most immuno-competent animals.
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Virome comparisons in wild-diseased and healthy captive giant pandas
BMC, 2017Co-Authors: Wen Zhang, Shixing Yang, Tongling Shan, Yan Wang, Peng Chen, Rong Hou, Zhijian Liu, Lianghua Guo, Xiaochun WangAbstract:Abstract Background The giant panda (Ailuropoda melanoleuca) is a vulnerable mammal herbivore living wild in central China. Viral infections have become a potential threat to the health of these endangered animals, but limited information related to these infections is available. Methods Using a viral metagenomic approach, we surveyed Viruses in the feces, nasopharyngeal secretions, blood, and different tissues from a wild giant panda that died from an unknown disease, a healthy wild giant panda, and 46 healthy captive animals. Results The previously uncharacterized complete or near complete genomes of four Viruses from three genera in Papillomaviridae family, six Viruses in a proposed new Picornaviridae genus (AimelVirus), two unclassified Viruses related to posaViruses in Picornavirales order, 19 anelloViruses in four different clades of Anelloviridae family, four putative circoViruses, and 15 Viruses belonging to the recently described Genomoviridae family were sequenced. Reflecting the diet of giant pandas, numerous Insect Virus sequences related to the families Iflaviridae, Dicistroviridae, Iridoviridae, Baculoviridae, Polydnaviridae, and subfamily Densovirinae and plant Viruses sequences related to the families Tombusviridae, Partitiviridae, Secoviridae, Geminiviridae, Luteoviridae, Virgaviridae, and Rhabdoviridae; genus UmbraVirus, Alphaflexiviridae, and Phycodnaviridae were also detected in fecal samples. A small number of Insect Virus sequences were also detected in the nasopharyngeal secretions of healthy giant pandas and lung tissues from the dead wild giant panda. Although the viral families present in the sick giant panda were also detected in the healthy ones, a higher proportion of papillomaViruses, picornaViruses, and anelloViruses reads were detected in the diseased panda. Conclusion This viral survey increases our understanding of eukaryotic Viruses in giant pandas and provides a baseline for comparison to Viruses detected in future infectious disease outbreaks. The similar viral families detected in sick and healthy giant pandas indicate that these Viruses result in commensal infections in most immuno-competent animals
Anette Schneemann - One of the best experts on this subject based on the ideXlab platform.
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Production and Application of Insect Virus-Based VLPs.
Methods in Molecular Biology, 2018Co-Authors: Radhika Gopal, Anette SchneemannAbstract:Virus-like particles (VLPs) are self-assembling platforms composed of viral structural proteins. They are used for a variety of purposes, ranging from the study of Virus assembly to vaccine development. VLPs can be produced in plants, bacteria, yeast, and Insect and mammalian cells. The baculoVirus expression system is one of the most commonly used systems for production of VLPs in eukaryotic cells. This chapter provides a brief overview of the main strategies used to generate recombinant baculoViruses and the applications of Insect Virus-derived VLPs in basic and applied research. It then describes detailed protocols for generation of recombinant baculoViruses, screening for their expression of VLPs in Insect cells, and VLP purification.
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Dissecting the Functional Domains of a Nonenveloped Virus Membrane Penetration Peptide
Journal of virology, 2009Co-Authors: Manidipa Banerjee, Anette Schneemann, Amy L. Odegard, Reza Khayat, Hanna E. Walukiewicz, John E JohnsonAbstract:Recent studies have established that several nonenveloped Viruses utilize Virus-encoded lytic peptides for host membrane disruption. We investigated this mechanism with the "gamma" peptide of the Insect Virus Flock House Virus (FHV). We demonstrate that the C terminus of gamma is essential for membrane disruption in vitro and the rescue of immature Virus infectivity in vivo, and the amphipathic N terminus of gamma alone is not sufficient. We also show that deletion of the C-terminal domain disrupts icosahedral ordering of the amphipathic helices of gamma in the Virus. Our results have broad implications for understanding membrane lysis during nonenveloped Virus entry.
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Formation of an RNA Heterodimer upon Heating of NodaVirus Particles
Journal of virology, 1999Co-Authors: Neel K. Krishna, Anette SchneemannAbstract:Flock House Virus is a small icosahedral Insect Virus of the family Nodaviridae. Its genome consists of two positive-sense RNA molecules, which are believed to be encapsidated into a single viral particle. However, evidence to support this claim is circumstantial. Here we demonstrate that exposure of nodaVirus particles to heat causes the two strands of viral RNA to form a stable complex, directly establishing that both RNAs are copackaged into one virion. The physical properties of the RNA complex, the effect of heat on the particles per se, and the possible relevance of these findings to the nodaVirus life cycle are presented.