| a baculovirus alkaline nuclease knockout construct produces fragmented dna and aberrant capsids. | dna replication of bacmid-derived constructs of the autographa californica multiple nucleocapsid nucleopolyhedrovirus (acmnpv) was analyzed by field inversion gel electrophoresis (fige) in combination with digestion at a unique eco81i restriction enzyme site. three constructs were characterized: a parental bacmid, a bacmid deleted for the alkaline nuclease gene, and a bacmid from which the gp64 gene had been deleted. the latter was employed as a control for comparison with the alkaline nuclease ... | 2007 | 17046043 |
| an orip/ebna-1-based baculovirus vector with prolonged and enhanced transgene expression. | the baculovirus autographa californica multiple nucleopolyhedrovirus (acmnpv) has been explored as a gene delivery vehicle for a variety of mammalian cell lines. however, the transient expression nature due to its incapability to replicate in mammalian cells and insufficient transduction efficiency limit its application. | 2006 | 17051599 |
| functional role of the cytoplasmic tail domain of the major envelope fusion protein of group ii baculoviruses. | f proteins from baculovirus nucleopolyhedrovirus (npv) group ii members are the major budded virus (bv) viral envelope fusion proteins. they undergo furin-like proteolysis processing in order to be functional. f proteins from different baculovirus species have a long cytoplasmic tail domain (ctd), ranging from 48 (spodoptera litura multicapsid npv [mnpv]) to 78 (adoxophyes honmai npv) amino acid (aa) residues, with a nonassigned function. this ctd is much longer than the ctd of gp64-like envelop ... | 2006 | 17071930 |
| characterization of antheraea pernyi nucleopolyhedrovirus p11 gene, a homologue of autographa californica nucleopolyhedrovirus orf108. | antheraea pernyi nucleopolyhedrovirus (apnpv) p11 gene is 309 bp long, potentially encoding 102 amino acids with a predicted molecular weight of 11.2 kda. apnpv p11 gene was cloned into the prokaryotic expression vector pqe-30 and p11 was expressed in e. coli m15. polyclonal antiserum was made against 6xhis tagged p11 protein expressed in e. coli m15. p11 gene transcription was detected as early as 36 h post-infection (p.i.) in tussah pupa and remain at high level up to 96 h p.i. structural loca ... | 2007 | 17072759 |
| characterization of acmnpv with a deletion of me53 gene. | the autographa californica multiple nucleopolyhedrovirus (acmnpv) me53 gene, which was previously reported as one of the major early-transcribed genes, was deleted through homologous recombination from an acmnpv genome propagated as a bacmid dna in e. coli, generating a me53 gene knockout bacmid. green fluorescent protein (gfp) expression analysis and supernatant passage assay revealed that the me53 knockout bacmid was unable to replicate in cell culture, while me53 repair bacmid, which was gene ... | 2007 | 17096186 |
| in vivo gene transfer into the honeybee using a nucleopolyhedrovirus vector. | the honeybee apis mellifera l. is a social insect and one of the most industrially important insects. we examined whether a baculovirus-mediated retrotransposon is applicable to in vivo transfer of exogenous genes to the honeybees. honeybee larvae and pupae were injected with two types of recombinant autographa californica nucleopolyhedrovirus (acnpv) vectors, one that includes the enhanced green fluorescent protein gene (egfp) as a reporter to be inserted into the honeybee genome, and another t ... | 2007 | 17125735 |
| p13 of leucania separata multiple nuclear polyhedrosis virus affected the polyhedra and budded virions yields of acmnpv. | p13 gene was first described by our laboratory in leucania separata multiple nuclear polyhedrovirus (ls-p13, orf114) back to 1995. however, the functions of ls-p13 and its reported homologues remained unknown. in order to probe the function of ls-p13, recombinant autographa californica nucleopolyhedroviruses (racmnpvs) were constructed to express ls-p13 in the sf9 cells at early, late or early/late phase. observations of microscope showed that the expression of ls-p13 could decrease the yield of ... | 2007 | 17141348 |
| the homingbac baculovirus cloning system: an alternative way to introduce foreign dna into baculovirus genomes. | an in vitro baculovirus cloning system has been developed for direct cloning of foreign dna into baculovirus genomes. this system is called the "homingbac system" because it uses homing endonucleases. the homingbac system was engineered into the baculoviruses acmnpv, bmnpv, pxmnpv, romnpv, hasnpv and hzsnpv. all homingbac viruses were designed to retain the polyhedra phenotype so that they could be inoculated per os to insects. this is the first time a common in vitro baculovirus cloning system ... | 2007 | 17141883 |
| mutational analysis of active site residues of chitinase from bombyx mori nucleopolyhedrovirus. | infection of bombyx mori larvae with b. mori nucleopolyhedrovirus (bmnpv) results in liquefaction of the host. this process is attributed to the synergistic action of two virus-encoded genes, chitinase (v-chia) and cathepsin (v-cath). previous studies have suggested that autographa californica nucleopolyhedrovirus (acmnpv) cath cannot be processed within infected cells in the absence of acmnpv chia. to investigate the interactions between v-chia and v-cath, we generated a recombinant bmnpv (103c ... | 2007 | 17145091 |
| bv/odv-e26: a palmitoylated, multifunctional structural protein of autographa californica nucleopolyhedrovirus. | autographa californica nucleopolyhedrovirus ac16 is 1 of 17 genes conserved within type 1 nucleopolyhedroviruses. this report demonstrates that multiple isoforms of the protein encoded by ac16, bv/odv-e26 (e26), are present in the infected cell. one form of e26 associates with viral dna or dna-binding proteins, while a second form associates with intracellular membranes and this is likely due to palmitoylation. the different forms of e26 present unique epitopes that can be discriminated by antis ... | 2007 | 17169392 |
| group i but not group ii npv induces antiviral effects in mammalian cells. | nucleopolyhedrovirus (npv) is divided into group i and group ii based on the phylogenetic analysis. it has been reported that group i npvs such as autographa californica multiple npv (acmnpv) can transduce mammalian cells, while group ii npvs such as helicoverpa armigera single npv (hasnpv) cannot. here we report that acmnpv was capable of stimulating antiviral activity in human hepatoma cells (smmc-7721) manifested by inhibition of vesicular stomatitis virus (vsv) replication. in contrast, the ... | 2006 | 17172054 |
| optimization of baculovirus transduction on freestyle293 cells for the generation of influenza b/lee/40. | recombinant baculovirus expression vectors derived from the autographa californica nuclear polyhedrosis virus can serve as efficient gene-transfer vehicles for transient expression of recombinant proteins in a wide range of mammalian cell types and are able to produce multisubunit particles such as viruses or virus like particles. in this study, we constructed eight recombinant baculoviruses each containing one of the influenza b/lee/40 virus genes in a bidirectional expression cassette for simu ... | 2006 | 17172661 |
| acmnpv orf38 protein has the activity of adp-ribose pyrophosphatase and is important for virus replication. | the orf38 of autographa californica multiple nucleopolyhedrovirus (acmnpv), or acorf38, contains a conserved motif of nudix (nucleotide diphosphate x) superfamily. it has the highest homology with adp-ribose pyrophosphatase (adprase), a subfamily of nudix pyrophosphatase. in the current study, recombinant acorf38 protein was prepared and shown to have adprase activity, with a km of 204 microm, and k(cat) of 6.96 s(-1) at ph 8.0 and 5 mm mgcl2. the transcription of acorf38 was detected 2 h postin ... | 2007 | 17174373 |
| proteins associated with culex nigripalpus nucleopolyhedrovirus occluded virions. | occlusion-derived virions (odvs) of the nucleopolyhedrovirus of culex nigripalpus (cuninpv) were purified by ludox density gradient ultracentrifugation, and the proteins were separated by one-dimensional sodium dodecyl sulfate-polyacrylamide gel electrophoresis. proteins were identified by using edman sequencing, matrix-assisted laser desorption ionization-time of flight mass spectrometry, nanoelectrospray quadrupole time-of-flight mass spectrometry, or a combination of these methods. half of th ... | 2007 | 17301145 |
| increased plasma selenium levels correlate with elevated resistance of heliothis virescens larvae against baculovirus infection. | we reported that dietary selenium (se) impacted the growth and development of trichoplusia ni reared for many generations on diet containing extremely low levels of se. larvae had an elevated resistance to per os infection with a baculovirus. in this study, we examine how dietary se (in the form of selenite) affects the growth, development, and se content of heliothis virescens that have been laboratory reared for less than two years. larvae fed a commercial tobacco budworm diet supplemented wit ... | 2007 | 17316679 |
| function and oligomerization study of the leucine zipper-like domain in p13 from leucania separata multiple nuclear polyhedrosis virus. | the p13 gene is uniquely present in group ii nucleopolyhedroviruses (npvs) and some granuloviruses, but not in group i npvs. p13 gene was first described by our laboratory in leucania separatamultiple nuclear polyhedrosis virus (ls-p13) in 1995. however, the functions of ls-p13 and of its homologues are unknown. when ls-p13 was inserted into autographa californica nucleopolyhedrovirus, a group i npv, polyhedra yield was inhibited. however, this inhibition was prevented when the leucine zipper-li ... | 2007 | 17394774 |
| characterization of a baculovirus lacking the dbp (dna-binding protein) gene. | autographa californica multiple nucleopolyhedrovirus (acmnpv) encodes two proteins that possess properties typical of single-stranded dna-binding proteins (ssbs), late expression factor-3 (lef-3), and a protein referred to as dna-binding protein (dbp). whereas lef-3 is a multi-functional protein essential for viral dna replication, transporting helicase into the nucleus, and forms a stable complex with the baculovirus alkaline nuclease, the role for dbp in baculovirus replication remains unclear ... | 2007 | 17449080 |
| the autographa californica m nucleopolyhedrovirus fibroblast growth factor accelerates host mortality. | the fibroblast growth factor (vfgf) gene encoded by autographa californica m nucleopolyhedrovirus (acmnpv) has been shown to share functional properties with cellular fgfs; it is a secreted protein, binds heparin, and stimulates motility of insect cells. we previously reported that viruses containing or lacking vfgf produced similar yields of budded virus and had similar kinetics of viral dna and protein syntheses in cultured cells. in this study, we characterized these viruses in two permissive ... | 2007 | 17459443 |
| the acmnpv pp31 gene is not essential for productive acmnpv replication or late gene transcription but appears to increase levels of most viral transcripts. | the pp31 gene of autographa californica multicapsid nucleopolyhedrovirus (acmnpv) encodes a phosphorylated dna binding protein that associates with virogenic stroma in the nuclei of infected cells. prior studies of pp31 by transient late expression assays suggested that pp31 may play an important role in transcription of acmnpv late genes [todd, j. w., passarelli, a. l., and miller, l. k. (1995). eighteen baculovirus genes, including lef-11, p35, 39k, and p47, support late gene expression. j. vi ... | 2007 | 17467768 |
| the heptad repeats region is essential for acmnpv p10 filament formation and not the proline-rich or the c-terminus basic regions. | baculovirus p10 protein is a small conserved protein and is expressed as bundles of filaments in the host cell during the late phase of virus infection. so far the published results on the domain responsible for filament structural formation have been contradictory. electron microscopy revealed that the c-terminus basic region was involved in filament structural formation in the autographa californica multiple nucleocapsid nucleopolyhedrovirus (acmnpv) [van oers, m.m., flipsen, j.t., reusken, c. ... | 2007 | 17481692 |
| ac18 is not essential for the propagation of autographa californica multiple nucleopolyhedrovirus. | orf18 (ac18) of autographa californica multiple nucleopolyhedrovirus (acmnpv) is a highly conserved gene in lepidopteran nucleopolyhedroviruses, but its function remains unknown. in this study, an ac18 knockout acmnpv bacmid was generated to determine the role of ac18 in baculovirus life cycle. after transfection of sf-9 cells, the ac18-null mutant showed similar infection pattern to the parent virus and the ac18 repair virus with respect to the production of infectious budded virus, occlusion b ... | 2007 | 17573091 |
| the n-terminal hydrophobic sequence of autographa californica nucleopolyhedrovirus pif-3 is essential for oral infection. | the autographa californica nucleopolyhedrovirus (acmnpv) open reading frame 115 has been identified as a per os infection factor (pif-3) and is essential for oral infection. here, we have characterized the pif-3 of acmnpv in more detail. the pif-3 transcripts were detected from 12 to 96 h post-infection (hpi) in sf9 cells infected with acmnpv. polyclonal antiserum first recognized a 25-kda protein at 36 hpi. western blot analysis indicated that pif-3 is a component of occlusion-derived virus but ... | 2007 | 17585368 |
| characterization of baculovirus constructs lacking either the ac 101, ac 142, or the ac 144 open reading frame. | to investigate the role of the gene products encoded from the open reading frames 101, 142, and 144 of autographa californica multiple nucleopolyhedrovirus (acmnpv), a set of bacmid knockout and repair constructs were generated. the repair genes were engineered to contain an ha epitope tag at their c-termini. the results of transfection-infection assays and growth curve analyses showed that the ac 101, 142, and 144 genes were required for infectious virus production. to better characterize the r ... | 2007 | 17585983 |
| biosafety of recombinant and wild type nucleopolyhedroviruses as bioinsecticides. | the entomopathogenic autographa californica (speyer) nucleopolyhedrovirus (acmnpv) has been genetically modified to increase its speed of kill. the potential adverse effects of a recombinant acmnpv (acaait) as well as wild type acmnpv and wild type spodoptera littoralis npv (slnpv) were studied. cotton plants were treated with these viruses at concentrations that were adjusted to resemble the recommended field application rate (4 x 10(12) pibs/feddan, feddan = 4,200 m2) and 3rd instar larvae of ... | 2007 | 17617674 |
| stimulation of baculovirus transcriptome expression in mammalian cells by baculoviral transcriptional activators. | autographa californica multiple nucleopolyhedrovirus (acmnpv), the type species of the family baculoviridae, is an insect-specific virus that can enter a variety of mammalian cells. the potential of this versatile virus for protein expression or gene therapy in mammalian cells has become the focus of many studies. in most mammalian cells, transduced acmnpv genes are either not expressed or expressed at an extremely low level. here, we studied the effects of the two major acmnpv trans-activators, ... | 2007 | 17622620 |
| autographa californica multiple nucleopolyhedrovirus exon0 (orf141) is required for efficient egress of nucleocapsids from the nucleus. | autographa californica multiple nucleopolyhedrovirus (acmnpv) exon0 (orf141) has been shown to be required for the efficient production of budded virus (bv). the deletion of exon0 reduces the level of bv production by up to 99% (x. dai, t. m. stewart, j. a. pathakamuri, q. li, and d. a. theilmann, j. virol. 78:9633-9644, 2004); however, the function or mechanism by which exon0 affects bv production is unknown. in this study, we further elucidated the function of exon0 by investigating the locali ... | 2007 | 17626083 |
| molecular cloning and characterization of an inhibitor of apoptosis protein (iap) from the tiger shrimp, penaeus monodon. | the inhibitor of apoptosis proteins (iaps) play important roles in both apoptosis and innate immunity. here, we report the first cloning and characterization of a novel iap family member, pmiap, from penaeus monodon. the full-length pmiap cdna is 4769bp, with an orf encoding a protein of 698 amino acids. the pmiap protein contains three bir domains and a c-terminal ring domain, and its mrna was expressed in all analyzed tissues. in insect cells, pmiap, together with spodoptera frugiperda iap, ac ... | 2008 | 17628672 |
| prediction of recombinant protein production in an insect cell-baculovirus system using a flow cytometric technique. | the baculovirus expression vector system (bevs) utilising the autographa californica nucleopolyhedrovirus (acmnpv) is widely becoming the system of choice for the production of many recombinant protein products due to the high yields obtained. however, there is a need to develop a simple reliable on-line method to monitor the production of recombinant proteins that have no intrinsic reporter properties. here we utilise flow cytometry to measure cell size, granularity and dna content in a single ... | 2007 | 17643445 |
| biochemical characterization of sf9 sp-family-like protein factors reveals interesting features. | we earlier documented the involvement of novel sp-family-like protein factors in transcription from the autographa californica nucleopolyhedrovirus (acnpv) polyhedrin (polh) gene promoter [ramachandran et al. (2001) j. biol. chem. 276: 23440-23449]. these zinc-dependent sp-like factors bind to two putative sp-factor-binding motifs, present within the acsp sequence upstream of the polh promoter, with very high affinity (k(d) = 2.1 x 10(-12) m). like other polh-promoter-associated host transcripti ... | 2007 | 17653621 |
| purification and characterization of a recombinant rat prohaptoglobin expressed in baculovirus-infected sf9 insect cells. | to generate hemoglobin-free full-length haptoglobin the cdna encoding rat haptoglobin alphabeta subunits was cloned into shuttle vector pvt-bac-his and used to produce a recombinant baculovirus autographa californica nuclear polyhedrosis virus (acnpv) as an expression vector, named hpacnpv. recombinant virus was used to infect spodoptera frugiperda (sf9) insect cells. the 50 kda protein expressed was mostly secreted into the culture medium at relatively high titer (15 microg/ml) and was found to ... | 2007 | 17681809 |
| reprogramming the chia expression profile of autographa californica multiple nucleopolyhedrovirus. | expression of chia and v-cath rna and enzyme activity in wild-type autographa californica multiple nucleopolyhedrovirus (acmnpv) was compared with that of recombinant acmnpv viruses reprogrammed for expression of the endogenous chia. to establish a baseline for our recombinant acmnpv studies, we compared, for the first time, the temporal expression profiles of both acmnpv chia transcription and translation simultaneously. the rate of intracellular chitinase accumulation during acmnpv infection f ... | 2007 | 17698657 |
| development and characterization of a continuous cell line, afkm-on-h, from hemocytes of the european corn borer ostrinia nubilalis (hübner) (lepidoptera, pyralidae). | the corn borer, ostrinia nubilalis, is a very important pest in different countries, and the in vitro system of the insect could be a useful tool for isolation and characterization of the pathogens and physiological responses of the insect. in this context, a cell line was derived from the hemocytes of the european corn borer and was named afkm-on-h for, respectively, o. nubilalis, armand frappier, king mongkut institutes, and hemocytes. this cell line was initiated and maintained in ex-cell 400 ... | 2007 | 17846857 |
| the chitinase a from the baculovirus acmnpv enhances resistance to both fungi and herbivorous pests in tobacco. | biotechnology has allowed the development of novel strategies to obtain plants that are more resistant to pests, fungal pathogens and other agents of biotic stress. the obvious advantages of having genotypes with multiple beneficial traits have recently fostered the development of gene pyramiding strategies, but less attention has been given to the study of genes that can increase resistance to different types of harmful organisms. here we report that a recombinant chitinase a protein of the aut ... | 2008 | 17851776 |
| spread of recombinant autographa californica nucleopolyhedrovirus in various tissues of silkworm bombyx mori determined by real-time pcr. | a cassette harboring luciferase reporter driven by bombyx mori a3 promoter was transferred to the bacmid acdeltaegt to generate the recombinant virus acnpva3luc (where ac represents autographa californica, npv represents nucleopolyhedrovirus, and a3luc represents the firefly luciferase reporter cassette driven by the a3 promoter). recombinant baculovirus was injected into the hemocoele of newly ecdysed fifth instar larvae of the silkworm. the infection of virus in various silkworm tissues was de ... | 2008 | 17920555 |
| the p26 gene of the autographa californica nucleopolyhedrovirus: timing of transcription, and cellular localization and dimerization of product. | p26, an early acmnpv gene, codes for a 240-amino acid polypeptide of unknown function. primer extension analysis showed that the p26 transcripts, initiating at three clustered start sites, accumulated between 2 and 12 h post-infection, after which these transcripts declined in quantity. indirect immunofluorescence studies detected the p26 protein primarily dispersed in the cytoplasm of infected cells, although some staining of the nucleus was also observed. immunoblots of infected cell fractions ... | 2008 | 17935816 |
| tissue specificity of a baculovirus-expressed, basement membrane-degrading protease in larvae of heliothis virescens. | scathl is a cathepsin l-like cysteine protease from the flesh fly, sarcophaga peregrina, which digests components of the basement membrane during insect metamorphosis. a recombinant baculovirus (acmlf9.scathl) expressing scathl kills larvae of the tobacco budworm heliothis virescens significantly faster than the wild type virus and triggers melanization and tissue fragmentation shortly before death. the tissue fragmentation was assumed to be a direct consequence of basement membrane degradation ... | 2007 | 17959212 |
| molecular biology of the baculovirus occlusion-derived virus envelope. | study of the biology of the occlusion-derived virus (odv) of the baculovirus autographa californica nucleopolyhedrovirus provides opportunities to reveal new discoveries into the mechanism of several cellular pathways. the synchronous pulse of multiple odv envelope proteins that integrate into the endoplasmic reticulum (er) and traffic to the nuclear membranes on their way to the odv envelope provide a unique tool to study the mechanisms of integral membrane protein trafficking from the er to th ... | 2007 | 17979668 |
| display of heterologous proteins on gp64null baculovirus virions and enhanced budding mediated by a vesicular stomatitis virus g-stem construct. | the autographa californica multicapsid nucleopolyhedrovirus (acmnpv) gp64 envelope glycoprotein is essential for virus entry and plays an important role in virion budding. an acmnpv construct that contains a deletion of the gp64 gene is unable to propagate infection from cell to cell, and this defect results from both a severe reduction in the production of budded virions and the absence of gp64 on virions. in the current study, we examined gp64 proteins containing n- and c-terminal truncations ... | 2008 | 17989172 |
| the baculovirus p10 protein of autographa californica nucleopolyhedrovirus forms two distinct cytoskeletal-like structures and associates with polyhedral occlusion bodies during infection. | the role of the microtubule-associated p10 protein of baculoviruses is not yet understood. p10 has previously been linked with the formation of a number of cytoskeletal-like or cytoskeleton-associated structures in the nucleus and cytoplasm, thought to be involved in the morphogenesis of virus polyhedral occlusion bodies. the formation of these structures was studied by immunofluorescence laser scanning confocal microscopy in tn368 cells, a model system amenable to the study of virus interaction ... | 2008 | 17991504 |
| baculovirus envelope fusion proteins f and gp64 exploit distinct receptors to gain entry into cultured insect cells. | group ii nucleopolyhedroviruses (npvs), e.g. helicoverpa armigera (hear) npv and spodoptera exigua (se) mnpv (multiple npv), lack a gp64-like protein that is present in group i npvs, e.g. autographa californica (ac)mnpv, but have an unrelated envelope fusion protein named f. three acmnpv viruses were constructed by introducing acmnpv gp64, hearnpv f or semnpv f genes, respectively, into a gp64-negative acmnpv bacmid. sf21 cells were incubated with different amounts of inactivated budded virus to ... | 2007 | 18024899 |
| baculovirus-mediated immediate-early gene expression and nuclear reorganization in human cells. | baculovirus, autographa californica multiple nucleopolyhedrovirus (acmnpv), has the ability to transduce mammalian cell lines without replication. the general objective of this study was to detect the transcription and expression of viral immediate-early genes in human cells and to examine the interactions between viral components and subnuclear structures. viral capsids were seen in large, discrete foci in nuclei of both dividing and non-dividing human cells. concurrently, the transcription of ... | 2008 | 18042259 |
| autographa californica multiple nucleopolyhedrovirus ac142, a core gene that is essential for bv production and odv envelopment. | autographa californica multiple nucleopolyhedrovirus (acmnpv) ac142 is a baculovirus core gene and encodes a protein previously shown to associate with occlusion-derived virus (odv). to determine its role in the baculovirus life cycle, we used the acmnpv bacmid system to generate an ac142 deletion virus (acbac(ac142ko-ph-gfp)). fluorescence and light microscopy revealed that acbac(ac142ko-ph-gfp) exhibits a single-cell infection phenotype. titration assays and western blot confirmed that acbac(a ... | 2008 | 18045640 |
| induction of antitumor acquired immunity by baculovirus autographa californica multiple nuclear polyhedrosis virus infection in mice. | the baculovirus autographa californica multiple nuclear polyhedrosis virus (acmnpv) has been studied as a gene therapy vector. here, we demonstrated that acmnpv induces antitumor acquired immunity. these results suggest that acmnpv has the potential to be an efficient virus or tumor therapy agent which induces innate and acquired immunity. | 2008 | 18057182 |
| induction of natural killer cell-dependent antitumor immunity by the autographa californica multiple nuclear polyhedrosis virus. | wild-type autographa californica multiple nuclear polyhedrosis virus (acmnpv) infects a variety of mammalian cell types in vitro, but does not replicate in these cells. we investigated the effects of acmnpv in the induction of the immune response and tumor metastasis in mice. after intravenous injection, acmnpv was taken up by the liver and spleen, and preferentially infected dendritic cells (dcs) and b cells in the spleen; costimulatory molecules cd40, cd80, and cd86 were upregulated in the dcs ... | 2008 | 18059370 |
| conserved leucines in n-terminal heptad repeat hr1 of envelope fusion protein f of group ii nucleopolyhedroviruses are important for correct processing and essential for fusogenicity. | the heptad repeat (hr), a conserved structural motif of class i viral fusion proteins, is responsible for the formation of a six-helix bundle structure during the envelope fusion process. the insect baculovirus f protein is a newly found budded virus envelope fusion protein which possesses common features to class i fusion proteins, such as proteolytic cleavage and the presence of an n-terminal open fusion peptide and multiple hr domains on the transmembrane subunit f(1). similar to many vertebr ... | 2008 | 18094156 |
| expression of two heterologous proteins depends on the mode of expression: comparison of in vivo and in vitro methods. | the yield of two proteins, avidin and green fluorescent protein (gfp), expressed from a modified autographa californica nucleopolyhedrovirus (acmnpv), was compared in sf9 cell culture monolayer, sf21 cell suspension culture and intact spodoptera litura larvae. gfp expressed from the p10 promoter yielded up to 1.5% of total soluble protein in larvae, 20-fold higher than that in monolayer suspension culture. avidin, expressed from the polh promoter, yielded up to 2.3% of total soluble protein in l ... | 2008 | 18175154 |
| gp64 of group i nucleopolyhedroviruses cannot readily rescue infectivity of group ii f-null nucleopolyhedroviruses. | the genus nucleopolyhedrovirus (npv) of the family baculoviridae can be subdivided phylogenetically into two groups. the same division can be made on the basis of their budded virus (bv) envelope fusion protein. group i npvs are characterized by the presence of a gp64-like major envelope fusion protein, which is involved in viral attachment and the fusion of virus and cell membrane, and is required for budding of progeny nucleocapsids. group ii npvs have an envelope fusion protein unrelated to g ... | 2008 | 18198373 |
| characterization of the gene delivery properties of baculoviral-based virosomal vectors. | the current study reports the production of baculoviral-virosomal vectors consisting of lipoplexes and of the viral glycoprotein (gp64) of baculovirus autographa californica multiple nucleopolyhdrovirus (acmnpv). this study demonstrates that such complexes have an increased transfection capability in a number of cells, including undifferentiated h9 human embryonic stem h9hes cells compared to lipoplexes alone. the gp64-mediated enhancement of gene transfer of lipoplexes is inhibited by the addit ... | 2008 | 18207578 |
| characterization of an egyptian spodoptera littoralis nucleopolyhedrovirus and a possible use of a highly conserved region from polyhedrin gene for nucleopolyhedrovirus detection. | an egyptian isolate of spodoptera littoralis nucleopolyhedrovirus (splinpv) was tested for its potential as biocontrol agent in comparison to autographa californica multiple nucleopolyhedrovirus (acmnpv). comparative assays of splinpv and acmnpv against 2nd instar larvae of spodoptera littoralis revealed 4-fold greater susceptibility of s. littoralis to acmnpv than to splinpv based on lc50 values for the two viruses. the lt50s determined for splinpv and acmnpv using lc50 of the virus against 2nd ... | 2008 | 18215282 |
| functional analysis of the transmembrane (tm) domain of the autographa californica multicapsid nucleopolyhedrovirus gp64 protein: substitution of heterologous tm domains. | gp64, the major envelope glycoprotein of the autographa californica multicapsid nucleopolyhedrovirus (acmnpv) budded virion, is important for host cell receptor binding and mediates low-ph-triggered membrane fusion during entry by endocytosis. in the current study, we examined the functional role of the acmnpv gp64 transmembrane (tm) domain by replacing the 23-amino-acid gp64 tm domain with corresponding tm domain sequences from a range of viral and cellular type i membrane proteins, including o ... | 2008 | 18216100 |
| autographa californica multiple nucleopolyhedrovirus ac66 is required for the efficient egress of nucleocapsids from the nucleus, general synthesis of preoccluded virions and occlusion body formation. | although orf66 (ac66) of autographa californica multiple nucleopolyhedrovirus (acmnpv) is conserved in all sequenced lepidopteran baculovirus genomes, its function is not known. this paper describes generation of an ac66 knockout acmnpv bacmid mutant and analyses of the influence of ac66 deletion on the virus replication in sf-9 cells so as to determine the role of ac66 in the viral life cycle. results indicated that budded virus (bv) yields were reduced over 99% in ac66-null mutant infected cel ... | 2008 | 18241908 |
| extended budded virus formation and induction of apoptosis by an acmnpv fp-25/p35 double mutant in trichoplusia ni cells. | an autographa californica nucleopolyhedrovirus (acmnpv) mutant (acdefrt) isolated from virus-infected trichoplusia ni (tn-368) cells produced plasma membrane blebbing and caspase-3-like activity late in infection. it also synthesized less polyhedra, but displayed enhanced budded virus formation in tn-368 cells. this phenotype resulted from dual mutations in p35 and fp-25. in this study we showed that enhanced budded virus production occurs because the hourly rate of release of virus from acdefrt ... | 2008 | 18261819 |
| maintenance of insect cell cultures and generation of recombinant baculoviruses. | this unit describes the maintenance and care of insect cell cultures as well as the generation, purification, and storage of recombinant baculoviruses. procedures are included for maintenance and subculturing of insect cells and cotransfection of insect cells with linearized baculovirus dna and recombinant transfer plasmid containing the gene of interest. in the event that the linearized virus is not available, wild-type baculovirus (acmnpv) dna may be used to produce recombinant baculoviruses. ... | 2004 | 18265340 |
| proteomics computational analyses suggest that baculovirus gp64 superfamily proteins are class iii penetrenes. | members of the baculoviridae encode two types of proteins that mediate virus:cell membrane fusion and penetration into the host cell. alignments of primary amino acid sequences indicate that baculovirus fusion proteins of group i nucleopolyhedroviruses (npv) form the gp64 superfamily. the structure of these viral penetrenes has not been determined. the gp64 superfamily includes the glycoprotein (gp) encoded by members of the thogotovirus genus of the orthomyxoviridae. the entry proteins of other ... | 2008 | 18282283 |
| identification of acmnpv exon0 (ac141) domains required for efficient production of budded virus, dimerization and association with bv/odv-c42 and fp25. | the autographa californica multiple nucleopolyhedrovirus (acmnpv) late gene exon0 (ac141) is required for the efficient production of budded virus (bv). exon0 interacts with nucleopcapsid protein bv/odv-c42 and fp25 and enables egress of nucleocapsids from the nucleus to the cytoplasm. this study examines the functional domains of exon0 that play a role in bv production. six putative domains of the 261 amino acid exon0 were deleted and examined for functionality by determining their ability to r ... | 2008 | 18313716 |
| acmnpv ac143 (odv-e18) is essential for mediating budded virus production and is the 30th baculovirus core gene. | autographa californica multiple nucleopolyhedrovirus (acmnpv) ac143 (odv-e18) is a late gene that encodes for a predicted 9.6 kda structural protein that locates to the occlusion derived viral envelope and viral induced intranuclear microvesicles [braunagel, s.c., he, h., ramamurthy, p., and summers, m.d. (1996). transcription, translation, and cellular localization of three autographa californica nuclear polyhedrosis virus structural proteins: odv-e18, odv-e35, and odv-ec27. virology 222, 100-1 ... | 2008 | 18328526 |
| inhibition of autographa californica nucleopolyhedrovirus (acnpv) polyhedrin gene expression by dnazyme knockout of its serine/threonine kinase (pk1) gene. | dnazyme is known to selectively cleave rna at predetermined site. transfection of autographa californica nucleopolyhedrovirus (acnpv) infected sf9 cells with serine/threonine kinase (pk1) mrna specific dnazymes, dz1 and dz2 to cleave the viral coded (pk1) mrna in between 87th and 88th, and 250th and 251st nucleotide, respectively inhibited the pk1 mrna and its protein expressions. interestingly, polh mrna and protein expressions were also inhibited by these dnazymes despite their inability to cl ... | 2008 | 18353480 |
| baculovirus-mediated interferon alleviates dimethylnitrosamine-induced liver cirrhosis symptoms in a murine model. | the wild-type baculovirus autographa californica multiple nuclear polyhedrosis virus (acmnpv) infects a range of mammalian cell types in vitro but does not replicate in these cells. the current study investigated the in vivo effect of acmnpv in the mouse model of liver cirrhosis induced by the mutagen dimethylnitrosamine. intraperitoneal injection of acmnpv induced an immune response. the baculovirus was taken up by the liver and spleen where it suppressed liver injury and fibrosis through the i ... | 2008 | 18369328 |
| plant-mediated alteration of the peritrophic matrix and baculovirus infection in lepidopteran larvae. | the peritrophic matrix (pm) lines the midgut of most insects, providing protection to the midgut epithelial cells while permitting passage of nutrients and water. herein, we provide evidence that plant-mediated alteration of the pm contributes to the well-documented inhibition of fatal infection by autographa californica multiple nucleopolyhedrovirus (acmnpv) of heliothis virescens f. larvae fed cotton foliage. we examined the impact of the pm on pathogenesis using a viral construct expressing a ... | 2008 | 18374352 |
| roles of lef-4 and ptp/bvp rna triphosphatases in processing of baculovirus late mrnas. | the baculovirus autographa californica nucleopolyhedrovirus encodes two proteins with rna triphosphatase activity. late expression factor lef-4, which is an essential gene, is a component of the rna polymerase and also encodes the rna capping enzyme guanylyltransferase. ptp/bvp is also an rna triphosphatase, but is not essential for viral replication, possibly because its activity is redundant to that of lef-4. to elucidate the role of these proteins in mrna cap formation, a mutant virus that la ... | 2008 | 18385232 |
| characterization of bombyx mori nucleopolyhedrovirus with a deletion of bm118. | bombyx mori nucleopolyhedrovirus (bmnpv) orf118 (bm118) is homologous to autographa californica nucleopolyhedrovirus (acmnpv) orf142, one of the core genes existing in all baculovirus genomes sequenced to date, suggesting that bm118 plays a critical role in viral infection. in this study, the primary role of bm118 was investigated by using homologous recombination in escherichia coli to generate a bm118 knockout bacmid containing the bmnpv genome. in addition, the bm118 rescue bacmid was constru ... | 2008 | 18462822 |
| slow cell infection, inefficient primary infection and inability to replicate in the fat body determine the host range of thysanoplusia orichalcea nucleopolyhedrovirus. | thysanoplusia orichacea multicapsid nucleopolyhedrovirus (thormnpv) carrying an enhanced green fluorescent protein (egfp) gene expression cassette (vthgfp) was used to study host-range mechanisms. infection kinetics showed that vthgfp replication in sf21 cells was too slow to suppress cell growth. wide-host-range autographa californica mnpv (acmnpv) could speed up vthgfp infection and enhance the vthgfp infection rate in sf21 cells. the enhancement was not due to recombination, as no recombinant ... | 2008 | 18474556 |
| characterization of acmnpv with a deletion of ac68 gene. | orf68 (ac68) of autographa californica multiple nucleopolyhedrovirus (acmnpv) is a highly conserved gene that codes a predicted 192-amino acid protein, but its function remains unknown. results of the current study showed that ac68 was transcribed from 3 to 96 h and the protein was detected from 36 to 96 h post infection. an ac68 knockout bacmid was generated to investigate the role of the gene in baculovirus life cycle. analyses of the production of infectious budded virus, occlusion bodies, an ... | 2008 | 18483845 |
| cooperation of ie1 and p35 genes in the activation of baculovirus acmnpv and hznv-1 promoters. | hznv-1 is a non-occluded virus belongs to the family of the baculovirus. one of the first detectable transcripts expressed by hznv-1 virus infection is a 6.2 kb gene, hhi1, located in the hindiii-i fragment of the viral genome. here we show that infection of baculovirus autographa californica multiple nucleopolyhedrovirus (acmnpv) could activate the expression of the hhi1 promoter. by using constructs containing progressive deletions of the upstream regulatory regions of the hhi1 gene, we demons ... | 2008 | 18486255 |
| characterization of the autographa californica nucleopolyhedrovirus ubiquitin gene promoter. | autographa californica multicapsid nucleopolyhedrovirus (acmnpv) encodes an ubiquitin protein, which may be involved in virus infection. functional analysis of the acmnpv ubiquitin promoter was performed by progressive deletion of sequence or mutation of putative cis-activating motifs in the promoter region. in the presence of viral factors, a transient expression assay demonstrated that the active regions responsive to promoter transcription are mainly located within the range of -595 to -382 b ... | 2008 | 18533474 |
| quantitative analysis of cytoplasmic actin gene promoter and nuclear polyhedrosis virus immediate-early promoter activities in various tissues of silkworm bombyx mori using recombinant autographa californica nuclear polyhedrosis virus as vector. | cassettes harboring luciferase reporter driven by bombyx mori cytoplasmic actin gene promoter (a3) (671 bp) and b. mori nuclear polyhedrosis virus immediate-early promoter (ie-1) (580 bp) were transferred to the bacmid acdeltaegt to generate the recombinant autographa californica nuclear polyhedrosis viruses, acnpva3luc and acnpvieluc, respectively. recombinant baculoviruses were injected into the hemocoele of newly ecdysed 5th instar larvae. the activities of the a3 and ie-1 promoters in variou ... | 2008 | 18535752 |
| effects of acp26 on in vitro and in vivo productivity, pathogenesis and virulence of autographa californica multiple nucleopolyhedrovirus. | homologs to autographa californica multiple nucleopolyhedrovirus (acmnpv) open reading frame (orf) 136 or acp26 are present within almost all nucleopolyhedroviruses (npvs). two copies of the gene are found in some members of group ii npvs, suggesting that it may play an important role in transmission or replication. phylogenetic analysis revealed that the predicted protein has some similarity with camelpox virus v-slfn protein, which reduces the virulence of orthopoxviruses in vivo. to investiga ... | 2008 | 18538883 |
| a functional f analogue of autographa californica nucleopolyhedrovirus gp64 from the agrotis segetum granulovirus. | the envelope fusion protein f of plutella xylostella granulovirus is a computational analogue of the gp64 envelope fusion protein of autographa californica nucleopolyhedrovirus (acmnpv). granulovirus (gv) f proteins were thought to be unable to functionally replace gp64 in the acmnpv pseudotyping system. in the present study the f protein of agrotis segetum gv (agsegv) was identified experimentally as the first functional gp64 analogue from gvs. agsef can rescue virion propagation and infectivit ... | 2008 | 18562524 |
| alginate concentration: a key factor in growth of temperature-sensitive baculovirus-infected insect cells in microcapsules. | the desire to increase cell density and product concentration has been the primary driving force for the development of better animal cell culture processes. in the technique used in our laboratory-microencapsulation-insect cells (spodoptera frugiperda), infected with a temperature-sensitive mutant of the autographa californica nuclear polyhedrosis virus (acnpv), were cultured in multiple membrane alginate-polylysine (pll) microcapsules which had a controlled membrane molecular-weight cutoff and ... | 1989 | 18588202 |
| a structured dynamic model for the baculovirus infection process in insect-cell reactor configurations. | a mathematical description of the infection of insect cells with baculovirus in a continuously operated reactor configuration is presented. the reactor configuration consists of one bioreactor in which insect cells (spodoptera frugiperda) are grown followed by one or two bioreactors in which cells are infected by a baculovirus (autographa californica nuclear polyhedrosis virus). it was demonstrated that the so-called passage effect is responsible for the observed difference in run time between a ... | 1992 | 18601149 |
| a bacmid approach to the genetic manipulation of granuloviruses. | a cydia pomonella granulovirus (cpgv) bacmid has been constructed, which allows rapid and efficient production of recombinant baculoviruses in escherichia coli. an 8.6kbp bacterial dna cassette derived from the acmnpv bac-to-bac system was ligated into a unique paci restriction site within an intergenic region flanking the dna ligase gene of the cpgv genome. the cpgv bacmids produced in e. coli were transfected into a cpgv-permissive c. pomonella cell line and the transfected cells fed to larvae ... | 2008 | 18602169 |
| analysis of inactivation of acmnpv under various conditions by the elva method. | inactivation of baculoviruses was examined under various conditions by elva, which enzymatically labels the virus envelope with radioisotopes and detects the labeled viruses by host cell-specific binding. when baculoviruses were incubated in a 50-ml culture tube, they rapidly lost infective ability by more than 75% of the initial titer in 2 h even at an insect cell cultivation temperature of 27 degrees c. altering ph from neutral significantly decreased the virus titer. repetition of freezing an ... | 2008 | 18603767 |
| production of recombinant proteins in high-density insect cell cultures. | the effect of the growth phase of spodoptera frugiperda (sf9) cells on the production of recombinant proteins (beta-galactosidase and glucocerebrosidase) was investigated. cells infected with the recombinant autographa californica nuclear polyhedrosis virus at the late exponential and stationary phases yielded low quantities of expressed protein. highest enzyme yields were obtained using sf9 cells from the early exponential phase (0.9 mg beta-galactosidase/10(6) cells and 1.7 microg glucocerebro ... | 1993 | 18612984 |
| on the origin of the polyhedral protein of autographa californica nuclear polyhedrosis virus. isolation, characterization, and translation of viral messenger rna. | virus-specific messenger rna was isolated 24 hr postinfection from spodoptera frugiperda cells infected with autographa californica nuclear polyhedrosis virus (acnpv) by means of hybridization with viral dna that was coupled to cellulose. viral mrna was analyzed on isokinetic sucrose gradients and on polyacrylamide gels containing 98% formamide. viral mrna was also translated in an in vitro protein-synthesizing system derived from wheat germ. one product comigrated with purified acnpv polyhedral ... | 1980 | 18631636 |
| autographa californica nuclear polyhedrosis virus-induced proteins in tissue culture. | the multiplication of autographa californica nuclear polyhedrosis virus was studied in trichoplusia ni and spodoptera frugiperda insect cell lines. using pulse labeling, 18 viral-induced proteins were identified by polyacrylamide gel electrophoresis. based on infectivity curves and protein synthesis studies, replication could be divided into four phases. during the early phase of infection, four viral-induced proteins with molecular weights of 45, 35, 34, and 31 thousand daltons could be detecte ... | 1980 | 18631644 |
| protease degradation of autographa californica nuclear polyhedrosis virus proteins. | the autographa californica nuclear polyhedrosis virus (ac-npv) occlusion bodies produced in vivo contained a protease which degraded occlusion body matrix protein and polypeptides of enveloped nucleocapsids during alkaline dissolution. the protease activity was required for complete dissociation of occlusion body matrix protein from the viral membrane during alkali liberation of the virus from occlusion bodies. in addition protease activity was required for the subsequent removal of the viral me ... | 1980 | 18631654 |
| protein synthesis in cells infected by autographa californica nuclear polyhedrosis virus (ac-npv): the effect of cytosine arabinoside. | twenty-two virion polypeptides (vp) were detected reproducibly when the occluded form (ov) of [35s]methionine-labeled ac-npv, purified from polyhedral inclusion bodies (pib), was analyzed by polyacrylamide gel electrophoresis and autoradiography. ten of the vps and the polyhedral protein (pp) were phosphorylated and 6 vps were glycoproteins. purified, nonoccluded virus (nov) revealed 25 polypeptides. during a single cycle of virus replication, the synthesis of 33 infected cell polypeptides (1cp) ... | 1980 | 18631655 |
| isolation and replication of an occlusion body-deficient mutant of the autographa californica nuclear polyhedrosis virus. | a spontaneous mutant of the autographa californica nuclear polyhedrosis virus which was deficient in viral occlusion body formation was studied in trichoplusia ni tissue culture cells. virus multiplication could be divided into four phases based on growth curves and the sequential appearance of 25 viral-induced proteins identified by pulse labeling and polyacrylamide gel electrophoresis. during the latent phase, five viral-induced proteins with molecular weights of 68, 47, 35, and 30 thousand (k ... | 1980 | 18631676 |
| in vivo pathway of autographa californica baculovirus invasion and infection. | the pathway of autographa californica nuclear polyhedrosis virus (acnpv) infection in cabbage looper, trichoplusia ni, larval midgut cells was studied by ultrastructural and virus titration methods. enveloped virions interacted with microvilli of columnar cells resulting in apparent fusion of the viral envelope and microvillus membrane. after entry into the cell cytoplasm, the intact nucleocapsids appeared to enter the nucleus through nuclear pores, and uncoating of the viral genome took place i ... | 1981 | 18635031 |
| autographa californica nuclear polyhedrosis virus phosphoproteins and synthesis of intracellular proteins after virus infection. | polypeptides and phosphoproteins isolated from nuclear and cytoplasmic fractions of tn-368-10 cells infected with autographa californica nuclear polyhedrosis virus (acmnpv) were analyzed by polyacrylamide gel electrophoresis. likewise, acmnpv extracellular virus and alkali-released virus were compared. acmnpv extracellular virus possessed at least nine phosphoproteins while the alkali-released virus had about 14 phosphoproteins. the major structural polypeptide of acmnpv, polyhedrin, was phospho ... | 1981 | 18635034 |
| cell culture studies with the imc-hz-1 nonoccluded virus. | studies were conducted on an adventitious agent (hz-1v) isolated from the imc-hz-1 cell line. it appeared identical to the virus first obtained by granados et al (r. r. granados, t. nguyen, and b. cato, 1978, intervirology, 10, 309-317) from a persistent infection of this cell line. restriction endonuclease digestion of hz-1v dna indicated the agent was different from the s nuclear polyhedrosis virus (hzsnpv) of the host species, heliothis zea, from which the imc-hz-1 cell line was derived by hi ... | 1981 | 18635105 |
| alteration of autographa californica nuclear polyhedrosis virus dna upon serial passage in cell culture. | plaque-purified autographa californica nuclear polyhedrosis virus, acmnpv e2 isolate, was propagated for 30 generations by serial passage in tn-368 cells. after passage, the dnas from 7 of 20 replaque-purified isolates were found to have additional ecori restriction enzyme fragments. these 7 isolates were of three types. the additional ecori fragments of each isolate hybridized to existing viral dna. restriction enzyme mapping with saci and smai show that isolates of each type contain an inserti ... | 1982 | 18635147 |
| inhibition of autographa californica nuclear polyhedrosis virus replication in high-density trichoplusia ni cell cultures. | replication of the autographa californica nuclear polyhedrosis virus was studied in trichoplusia ni (tn-368) tissue culture cells under cell density conditions which approximated a confluent monolayer (5.7 x 10(5) cells/cm(2) growth surface). these high-density cultures were not refractory to infection but the synthesis of both the occluded and nonoccluded forms of the virus were inhibited greater than 98% when compared to inoculation of low cell density cultures (1.4 x 10(5) cells/cm(2)). the i ... | 1982 | 18635148 |
| expression of green fluorescent protein in insect larvae and its application for heterologous protein production. | many eukaryotic proteins have been successfully expressed in insect cells infected with a recombinant baculovirus derived from the autographa californica nuclear polyhedrosis virus (acnpv). there are, however, disadvantages with this cell-based system when carried out in suspension cultures at high bioreactor volume (e.g., limited oxygen transfer, susceptibility to contamination, high cost). these problems can be avoided by using whole larvae as the "reactors." there are, however, other problems ... | 1997 | 18636639 |
| characterization of monoclonal antibodies to the autographa californica nuclear polyhedrosis virus. | mouse hybridomas which produce monoclonal antibodies to the autographa californica nuclear polyhedrosis virus (acnpv) have been prepared and the protein to which each is directed has been determined. the antibody produced by clones 3f3 and 5e9 specifically bound polyhedron protein of mw 32,000 when used in immunoadsorption chromatography when used in elisa they could not distinguish between insect- and cell culture-derived polyhedron protein and also reacted with a wide range of baculoviruses. t ... | 1982 | 18638810 |
| dna homology among subgroup a, b, and c baculoviruses. | the dna homology among 18 baculoviruses from subgroups a, b, and c was compared using restriction endonuclease analysis, dna hybridization, and southern blot hybridization. restriction enzyme patterns for each of the viral dnas compared was unique. viral dna homology was evaluated by hybridizing 32p-labeled viral dnas to unlabeled dnas immobilized on nitrocellulose filters. hybridization conditions were varied by using a range of formamide concentrations during annealing. the apparent dna homolo ... | 1982 | 18638848 |
| characterization of two abundant mrnas of autographa californica nuclear polyhedrosis virus present late in infection. | cytoplasmic poly(a)(+) rna isolated from spodoptera frugiperda cells late after infection with autographa californica nuclear polyhedrosis virus (30-40 hr pi) was fractionated according to size on denaturing methyl mercury gels. two major rna species (1.4 kb and 0.75 kb) and several minor rna species were detected by ethidium bromide staining. the predominant rna species of about 1.4 kb was considered to be polyhedrin mrna because (1) in vitro translation of the rna, which was eluted from methyl ... | 1983 | 18638868 |
| a temperature-sensitive mutant of the baculovirus autographa californica nuclear polyhedrosis virus defective in an early function required for further gene expression. | fifteen temperature-sensitive (ts) mutants of the baculovirus autographa californica nuclear polyhedrosis virus (acnpv) have been analyzed by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (sds-page) of proteins synthesized in infected cells. one of the mutants, tsb821, was found to be defective in a very early function. seven virus-induced proteins were synthesized by 2 hr postinfection. in marked contrast to wild-type virus and the other 14 ts mutants, the synthesis of further virus ... | 1983 | 18638939 |
| mapping early transcription products of autographa californica nuclear polyhedrosis virus. | the regions of the acmnpv genome represented as cytoplasmic transcripts early after infection of spodoptera frugiperda cells prior to and encompassing the initiation of dna replication were mapped. in vivo(32)p pulse-labeled cytoplasmic rna from infected cells at various times postinfection was used to probe southern blots of cloned ecori acmnpv dna fragments. at the earliest time point studied (0.5 - 2.5 hr p.i.) transcripts represented a large proportion of the genome although specific regions ... | 1983 | 18638940 |
| a study of the glycoproteins of autographa californica nuclear polyhedrosis virus (acnpv). | pulse labeling with tritiated mannose was used to follow the time course of autographa californica nuclear polyhedrosis virus (acnpv) glycoprotein synthesis in spodoptera frugiperda iplb-21 cells. nine viral-induced intracellular glycoproteins were first detected from as early as 2 hr postinoculation (67k, early phase) to as late as 14 hr (36k and 19k glycoproteins, intermediate phase). glycosylation of these proteins was observed to continue to the end of the experiment (28 hr postinoculation). ... | 1983 | 18639173 |
| nucleotide sequence of the polyhedrin gene of autographa californica nuclear polyhedrosis virus. | the nucleotide sequence of a 1143-bp region of autographa californica mnpv (acmnpv) dna containing the entire coding region of polyhedrin was determined. the coding region consisted of 732 bp without intervening sequences. the 5' leader sequence was approximately 58 nucleotides in length. a putative "tata box" and "caat box" were located 20 and 52 bp upstream from the transcriptional start site, respectively. two tandem repeats of 8 bp were found 70 and 84 bp upstream from the transcriptional st ... | 1983 | 18639177 |
| budded autographa californica npv 64k protein: further biochemical analysis and effects of postimmunoprecipitation sample preparation conditions. | previously it was shown that acv1, a neutralizing monoclonal antibody of the autographa californica nuclear polyhedrosis virus-budded phenotype reacted with a surface antigen present on infected cells during virus budding, and in the viral envelope (l. e. volkman, p. a. goldsmith, r. t. hess, and p. faulkner (1984), virology 133, 354-362). radioimmune precipitation of solubilized, [35s]methionine-labeled budded virus with acv1 and analysis on sds-page revealed four bands consistently: one major ... | 1984 | 18639832 |
| nucleotide sequence of the p10 polypeptide gene of autographa californica nuclear polyhedrosis virus. | a portion of the autographa californica nuclear polyhedrosis virus genome lying within the ecori-p region of the physical map has been sequenced. previous studies employing northern blotting and in vitro translation had shown that this region encoded the gene for a "late" 8-10k polypeptide [d. z. rohel, m. a. cochran, and p. faulkner, virology 124, 357-365, (1983); g. e. smith, j. m. vlak, and m. d. summers, j. virol.45, 215-225, (1983)]. the 1313-base pair region contained an open reading frame ... | 1984 | 18639833 |
| mechanism of neutralization of budded autographa californica nuclear polyhedrosis virus by a monoclonal antibody: inhibition of entry by adsorptive endocytosis. | autographa californica nuclear polyhedrosis virus (acnpv) is characterized by two different phenotypes, each with a specific role in the life cycle of the virus in nature. they differ widely in infectivity both in vivo and in vitro, and are neutralized by different populations of antibodies. a monoclonal antibody designated acv1 neutralizes one phenotype, bv, by reacting with a major envelope antigen not present on the other phenotype. bv can functionally enter cells by two different pathways an ... | 1985 | 18639849 |
| alternate pathway of entry of budded autographa californica nuclear polyhedrosis virus: fusion at the plasma membrane. | recently we reported that the budded phenotype of autographa californica nuclear polyhedrosis virus (aenpv bv) functionally entered iplb-sf-21 cells by adsorptive endocytosis and that neutralizing monoclonal antibody acv1 acted by preventing acnpv bv from using this entry pathway (l. e. volkman and p. a. goldsmith (1985), virology 143, 185-195). not all infectivity could be neutralized by acv1, however, and in the study reported herein we investigated the nature of the particles responsible for ... | 1986 | 18640581 |
| effect of tunicamycin on the structural proteins and infectivity of budded autographa californica nuclear polyhedrosis virus. | the budded phenotype of autograha californica nuclear polyhedrosis virus (acnpv bv) has a 64k glycoprotein in its envelope which is important in the ability of the virus to functionally enter host cells. tunicamycin (tm), an inhibitor of n-linked glycosylation, was used to determine whether the sugar moiety was essential for the normal function of the 64k protein. at 10 mug/ml tm, glycosylation was completely inhibited. infectivity of acnpv bv was reduced to 2% of control while extracellular par ... | 1986 | 18640650 |
| bcl-2 expression in spodoptera frugiperda sf-9 and trichoplusia ni bti-tn-5b1-4 insect cells: effect on recombinant protein expression and cell viability. | the effect of bcl-2 expression on cell viability and recombinant protein synthesis was investigated in the spodoptera frugiperda sf-9 and trichoplusia ni bti-tn-5b1-4 (high fivetrade mark) insect cell lines. it was found that coinfection with a baculovirus expressing bcl-2 [autographa californica nuclear polyhedrosis virus (acnpv)-bcl2] extended the life span of high fivetrade mark cells but not sf-9 cells when compared to infection with recombinant baculoviruses expressing either human tissue p ... | 1997 | 18642241 |
| evidence for microfilament involvement in budded autographa californica nuclear polyhedrosis virus production. | autographa californica nuclear polyhedrosis virus (acnpv) is a large, double-stranded dna virus that infects lepidopteran insects. in the course of infection two different forms of the virus are produced; one that serves to spread the infection from insect to insect and another that spreads the infection within the insect from cell to cell. the latter form matures by budding from the plasma membrane of infected cells. we have found that cytochalasins b and d prevent the production of infectious ... | 1987 | 18644552 |
| baculovirus-mediated gene transfer into mammalian cells. | a kind of cytotoxinic gene barnase was cloned downstream of immediate early promoter from cytomegalovirus (cmv). recombinant virus vaccmvbar was constructed using bac-to-bac system by insertion of the expression cassette into the polyhedrin gene locus of autographa californica nuclear polyhedrosis virus (acnpv). cytotoxinic effect caused by expression of barnase was observed in four mammalian cells after vaccmvbar infection dose-dependent analysis revealed that one of the cells hicam was the mos ... | 1998 | 18726228 |
| effects of temperature and shear force on infectivity of the baculovirus autographa californica m nucleopolyhedrovirus. | virus stability and infectivity during stressful conditions was assessed to establish guidelines for future virus filtration experiments and to contribute to the body of knowledge on a widely used virus. a recombinant baculovirus of autographa californica m nucleopolyhedrovirus (acmnpv), vhsgfp, was incubated at 15-65 degrees c. a 2-log decrease in virus infectivity occurred after virus incubation above 45 degrees c. the activation energy of virus deactivation was circa 108 kj/mol. dynamic light ... | 2008 | 18760306 |