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heterologous recombination between autographa californica nuclear polyhedrosis virus dna and foreign dna in non-polyhedrin segments of the viral genome.we used the expression vector system of autographa californica nuclear polyhedrosis virus (acnpv) and spodoptera frugiperda insect cells to study mechanisms of recombination in insect cells. we concentrated on the isolation and analysis of heterologous recombinants. the e1 region of human adenovirus type 2 (ad2) was inserted into regions of the acnpv genome which lacked apparent homologies to the polyhedrin region. out of a total of 122 recombinant acnpv plaques, which hybridized to ad2 dna in p ...19911962504
purification and functional characterization of the human beta 2-adrenergic receptor produced in baculovirus-infected insect cells.a human cdna fragment bearing the complete coding region for the beta 2-adrenergic receptor was introduced into the genome of autographa california nuclear polyhedrosis virus under the control of the polyhedrin promoter. binding studies using [125i]iodocyanopindolol showed that sf9 insect cells infected with the recombinant virus expressed approximately 1 x 10(6) beta 2-adrenergic receptors on their cell surface. photoaffinity labeling of whole cells and membranes revealed a molecular weight of ...19911645288
secretion of biologically active leech hirudin from baculovirus-infected insect cells.the thrombin inhibitor, hirudin, from the leech hirudo medicinalis, is the most powerful natural anticoagulant known. it has been characterized as a polypeptide of 65 amino acids which exhibits its anticoagulant properties by binding tightly and specifically to alpha-thrombin. the potency and specificity of hirudin have generated interest on its possible use in the treatment or prophylaxis of various thrombotic diseases. we have used the baculovirus expression system to efficiently produce activ ...19911647362
high level expression of dna polymerases from herpesviruses.the dna polymerase genes of human cytomegalovirus (hcmv) and varicella-zoster virus (vzv) were inserted separately into the polyhedrin gene of autographa californica nuclear polyhedrosis virus (acnpv) by cotransfection of spodoptera frugiperda (sf9) cells with baculovirus transfer vectors carrying the genes and acnpv infectious dna. infection of sf9 cells with the recombinant viruses resulted in expression from the polyhedrin promoter of proteins of the expected mrs. these proteins possessed dna ...19911649906
insect virus: assays for viral replication and persistence in mammalian cells.viral pesticidal agents must be evaluated for potential health hazards prior to utilization. assessment of the likelihood of replication in humans has included in vitro exposure of human cells to the potential pesticidal agent. previous in vitro evaluation strategies have lacked positive controls. thus, negative results, interpreted as no effect of the virus on human cells, could reflect basic deficiencies in the testing protocols. we designed a testing scheme for viral pesticides and used it to ...19911650786
functional expression of the human growth factor activatable na+/h+ antiporter (nhe-1) in baculovirus-infected cells.we constructed a recombinant baculovirus, based on autographa californica nuclear polyhedrosis virus, containing the human na+/h+ antiporter cdna under control of the polyhedrin promoter. when infected with this recombinant baculovirus, the sf9 cell line, derived from spodoptera frugiperda, expresses a fully functional na+/h+ antiporter as measured by the generation of an amiloride-sensitive na+ influx in response to an acid load. the na+/h(+)-exchange activity, not detectable in sf9 cells, emer ...19911654101
processing and antigenicity of entire and anchor-free spike glycoprotein s of coronavirus tgev expressed by recombinant baculovirus.the s gene of transmissible gastroenteritis virus (tgev) was inserted into the genome of autographa californica nuclear polyhedrosis virus (acnpv) using the transfer plasmid pvl941. infection of sf9 insect cells with the recombinant virus resulted in the synthesis of a 175k polypeptide which was able to trimerize and was transported to the cell surface as is the authentic tgev s protein. despite the lack of complete carbohydrate processing, the recombinant s protein exhibited antigenic propertie ...19911660201
a functional hepatitis b virus x protein produced in insect cells.we have constructed a recombinant baculovirus from autographa californica nuclear polyhedrosis virus, called acx, that expresses the gene encoding the hepatitis b virus x protein in infected spodoptera frugiperda (sf21ae) insect cells. a 16.5-kda monomer and a 33-kda dimer of the x protein were detected in extracts from acx-infected cells on immunoblots using a polyclonal anti-x antibody. the biological activity of the insect cell-produced x protein was assayed by fusing acx-infected sf21ae cell ...19911660211
characterization of pseudorabies virus neutralization antigen glycoprotein giii produced in insect cells by a baculovirus expression vector.the gene encoding the complete glycoprotein of pseudorabies virus (prv, yamagata-s81 strain glycoprotein giii) has been inserted into the baculovirus transfer vector pacym1s derived from the nuclear polyhedrosis virus of autographa californica (acnpv). a spodoptera frugiperda cell line, sf21ae, was efficiently co-transfected with the transfer vector containing the giii gene and acnpv dna by cationic liposomes (lipofectin). the gene was placed under the control of the acnpv polyhedrin promoter an ...19911661981
immunoselection of recombinant baculoviruses expressing high levels of biologically active herpes simplex virus type 1 glycoprotein d.the dna sequence encoding the complete herpes simplex virus type 1 (hsv-1) glycoprotein d (gd) was inserted into a baculovirus transfer vector under control of the polyhedrin gene promoter of the baculovirus autographa california nuclear polyhedrosis virus (acnpv). after co-transfection of spodoptera frugiperda (sf9) insect cells with wild-type acnpv dna and the recombinant transfer vector dna, polyhedrin-negative recombinants that expressed high levels of hsv-1 gd were isolated using immunoaffi ...19911662037
dna restriction polymorphism in wild isolates of spodoptera frugiperda nuclear polyhedrosis virus.restriction endonuclease analysis was used to examine variation in dna of 22 wild isolates of spodoptera frugiperda nuclear polyhedrosis virus (sfnpv). eleven of the 15 isolated from louisiana were distinguishable based on restriction fragment profiles from the enzymes bamhi, hindiii, and ecori. there was significant genetic variation in sfnpv isolates within single agricultural fields. nucleotide sequence divergence values, based on restriction fragment profiles, indicated that genetic variatio ...19911679452
temporal analysis and spatial mapping of lymantria dispar nuclear polyhedrosis virus transcripts and in vitro translation polypeptides.genomic expression of the lymantria dispar multinucleocapsid nuclear polyhedrosis virus (ldmnpv) was studied. viral specific transcripts expressed in cell culture at various times from 2 through 72 h postinfection were identified and their genomic origins mapped through northern analysis. sixty-five distinct transcripts were identified in this analysis. most viral transcripts were expressed late in infection, and originated from throughout the viral genome. viral polypeptides expressed in infect ...19911685048
transcription of the baculovirus polyhedrin gene reduces the levels of an antisense transcript initiated downstream.a late 3.2-kilobase (kb) rna initiated approximately 2 kb downstream of the 3' end of the autographa californica nuclear polyhedrosis virus polyhedrin-coding sequence and traversed the polyhedrin gene in an antisense direction. this rna was sense rna for the two open reading frames flanking the polyhedrin gene. a mutant virus, vxpoly, which differs from wild-type virus only at the essential rna initiation site in the polyhedrin promoter, exhibited higher levels of the 3.2-kb rna than did wild-ty ...19901692351
gene organization and transcription of ted, a lepidopteran retrotransposon integrated within the baculovirus genome.a single copy of the retrotransposon ted, from the moth trichoplusia ni (a lepidopteran noctuid), was identified within the dna genome of the baculovirus autographa californica nuclear polyhedrosis virus. determination of the complete nucleotide sequence (7,510 base pairs) of the integrated copy indicated that ted belongs to the family of retrotransposons that includes drosophila melanogaster elements 17.6 and gypsy and thus represents the first nondipteran member of this invertebrate group to b ...19901692964
categorizing some early and late transcripts directed by the autographa californica nuclear polyhedrosis virus.using an s1 mapping assay on rna from spodoptera frugiperda cells infected by the autographa californica nuclear polyhedrosis virus in the presence and absence of cycloheximide and aphidicolin, we can distinguish three classes of transcripts. first, there are those whose synthesis is blocked by the dna synthesis inhibitor aphidicolin and which are therefore late transcripts. these include the late transcript of the 39k gene and a late leftward transcript across the xhoi site in the hindiii-f reg ...19901698929
characterization of virus-like particles produced by a recombinant baculovirus containing the gag gene of the bovine immunodeficiency-like virus.the entire gag gene of the bovine immunodeficiency-like virus (biv) was inserted behind the strong polyhedron promoter of autographa californica nuclear polyhedrosis virus (acnpv). the resultant recombinant baculovirus (acnpv-bivgag) was used to infect insect cells in order to overexpress and characterize biv gag gene products. the infection resulted in the high-level expression of a protein similar in size to the predicted biv gag precursor (pr53gag). biv pr53gag was detected in acnpv-bivgag-in ...19901699349
expression of rat tyrosine hydroxylase in insect tissue culture cells and purification and characterization of the cloned enzyme.rat tyrosine hydroxylase has been expressed at high levels in spodoptera frugiperda cells using a baculovirus expression system. a cdna containing the coding region for pc12 tyrosine hydroxylase was inserted into the unique ecori site of the transfer vector pljc8 to yield the recombinant vector pljc9. spodoptera frugiperda cells were then co-infected with pljc9 and wild type autographa californica nuclear polyhedrosis virus. recombinant virus particles containing the cdna for tyrosine hydroxylas ...19901967606
expression of the human multidrug transporter in insect cells by a recombinant baculovirus.the plasma membrane associated human multidrug resistance (mdr1) gene product, known as the 170-kda p-glycoprotein or the multidrug transporter, acts as an atp-dependent efflux pump for various cytotoxic agents. we expressed recombinant human multidrug transporter in a baculovirus expression system to obtain large quantities and further investigate its structure and mechanism of action. mdr1 cdna was inserted into the genome of the autographa californica nuclear polyhedrosis virus under the cont ...19901970935
temporal expression of hiv-1 envelope proteins in baculovirus-infected insect cells: implications for glycosylation and cd4 binding.three different human immunodeficiency virus type i (hiv-1) envelope derived recombinant proteins and the full length human cd4 polypeptide were expressed in spodoptera frugiperda (sf9) cells. dna constructs encoding cd4, gp120, gp160, and gp160 delta (full length gp160 minus the transmembrane and cytoplasmic region of gp41) were cloned into the baculovirus expression vector pvl941 or a derivative and used to generate recombinant viruses in a cotransfection with dna from autographa californica n ...19902076345
expression of htlv-i envelope protein fused to hydrophobic amino-terminal peptide of baculovirus polyhedrin in insect cells and its application for serological assays.the envelope of human t-cell leukemia virus type i (htlv-i) consists of two glycoproteins gp46 and p20e. recombinant envelope proteins were produced by using an expression vector derived from insect baculovirus, bombyx mori nuclear polyhedrosis virus. polyhedrin fusion proteins c182, n147, and n287 contained whole region p20e, c-terminal half of gp46, and almost whole region gp46, respectively. n147 and n287 were suggested to be processed forms resulting from internal cleavage by cellular enzyme ...19902078412
[identification of nuclear polyhedrosis viruses by restriction analysis].the restriction endonucleases bam hi, pst i, sla i were used to study dna of nuclear polyhedrosis virus (npv) of bollworm, two npv isolates of cabbage moth, npv of black arches moth isolated from a natural population of caterpillars. the mean molecular sizes of virus genomes were calculated. genotypic differences between two isolates of cabbage moth npv were demonstrated. heterogeneity of a natural isolate of black arches moth npv was established.19902082555
synthesis of the membrane fusion and hemagglutinin proteins of measles virus, using a novel baculovirus vector containing the beta-galactosidase gene.an improved baculovirus expression vector was developed to expedite screening and facilitate oligonucleotide-directed mutagenesis. this vector contained twin promoters derived from the p10 and polyhedrin genes of autographica californica nuclear polyhedrosis virus. the p10 promoter directed the synthesis of beta-galactosidase, whereas the polyhedrin promoter controlled the synthesis of foreign gene products. these two genes recombined with wild-type virus genome to yield recombinants which were ...19902104544
expression of the bacillus anthracis protective antigen gene by baculovirus and vaccinia virus recombinants.the gene encoding bacillus anthracis protective antigen (pa) was modified by site-directed mutagenesis, subcloned into baculovirus and vaccinia virus plasmid transfer vectors (pacym1 and psc-11, respectively), and inserted via homologous recombinations into baculovirus autographa californica nuclear polyhedrosis virus or vaccinia virus (strains wr and connaught). expression of pa was detected in both systems by immunofluorescence assays with antisera from rabbits immunized with b. anthracis pa. ...19902105271
identifying the rna polymerases that synthesize specific transcripts of the autographa californica nuclear polyhedrosis virus.nuclear run-on assays carried out in the presence and absence of the rna polymerase ii inhibitor, alpha-amanitin, were used to determine the exact timing of the switch from inhibitor-sensitive transcription catalysed by host rna polymerase ii, to inhibitor-resistant transcription catalysed by the baculovirus-induced rna polymerase. these studies revealed that the onset of alpha-amanitin-resistant transcription is just after 6 h post-infection, simultaneous with the beginning of the late phase of ...19902106003
regulation of expression of a baculovirus ecdysteroid udpglucosyltransferase gene.the autographa californica nuclear polyhedrosis virus egt gene encodes an ecdysteroid udpglucosyltransferase which catalyzes the transfer of glucose from udpglucose to ecdysteroid insect molting hormones. expression of this gene allows the virus to block molting and pupation of infected insect larvae. in this study, we present the nucleotide sequence of the a. californica nuclear polyhedrosis virus egt gene and characterize egt gene expression at the transcriptional and translational levels. egt ...19902106039
response of nuclear polyhedrosis virus-resistant spodoptera frugiperda larvae to other pathogens and to chemical insecticides.selection in the laboratory for spodoptera frugiperda (sf) resistant to nuclear polyhedrosis virus (npv) affected the susceptibility of the insect to certain other mortality agents, including a chemical insecticide. median lethal concentrations (lc50s) and associated statistics were compared for several mortality agents between colonies of npv-resistant and -susceptible (control) insects. compared to the susceptible insects, the npv-resistant insects were cross-resistant to the s. frugiperda gra ...19902108223
a baculovirus expression vector derived from the basic protein promoter of autographa californica nuclear polyhedrosis virus.the basic protein of autographa californica nuclear polyhedrosis virus (acmnpv) is associated with virus dna in virion nucleocapsids and is produced in infected cells during the late phase of gene expression. a transfer vector was constructed containing the beta-galactosidase gene, under the control of a copy of the putative basic protein promoter, in place of the polyhedrin gene within the acmnpv ecori fragment i. after cotransfection of spodoptera frugiperda cells with the transfer vector and ...19902109042
localization of the 34 kda polyhedron envelope protein in spodoptera frugiperda cells infected with autographa californica nuclear polyhedrosis virus.using immuno-electron microscopy the 34 kda polyhedron envelope (pe) phosphoprotein (pp 34) was localized in cells infected with autographa californica multiple-nucleocapsid nuclear polyhedrosis virus (acmnpv). in wild-type acmnpv-infected cells this protein was found associated with electron-dense "spacers" and the polyhedron envelopes demonstrating their structural relationship. in these cells pp 34 was also found associated with fibrillar structures present in the nucleus and cytoplasm of inf ...19902109589
alpha 1----3-galactosyltransferase: the use of recombinant enzyme for the synthesis of alpha-galactosylated glycoconjugates.we have reported the isolation and characterization of a bovine cdna clone containing the complete coding sequence for udp-gal:gal beta 1----4glcnac alpha 1----3-galactosyltransferase [joziasse, d. h., shaper, j. h., van den eijnden, d. h., van tunen, a. j. & shaper, n. l. (1989) j. biol. chem. 264, 14290-14297]. insertion of this cdna clone into the genome of autographa californica nuclear polyhedrosis virus (acnpv) and subsequent infection of spodoptera frugiperda (sf9) insect cells with recom ...19902116309
expression and purification of p24, the core protein of hiv, using a baculovirus-insect cell expression system.the baculovirus autographa californica nuclear polyhedrosis virus (acnpv) has been genetically manipulated to yield a recombinant virus capable of expressing p24, the major core protein of hiv-1, in insect cell culture. the expressed product is a p24 protein flanked by short regions of p17 at the amino terminus and p12 at the carboxy terminus. it has been identified and characterized using monoclonal antibodies on western blots and by amino-terminal sequence analysis. the presence of p24 in the ...19902126440
co-expression of the human hla-b27 class i antigen and the e3/19k protein of adenovirus-2 in insect cells using a baculovirus vector.we have expressed the human mhc class i hla-b27 antigen, human beta 2-microglobulin, and the e3/19k protein of adenovirus-2 in spodoptera frugiperda insect cells (sf9) by using the autographa californica nuclear polyhedrosis virus. all genes were inserted under the strong polyhedrin promoter in the vector pvl941. the proteins were expressed at high levels, ranging from 1 to 8 mg protein per 3 x 10(9) cells. both a full-length and a truncated form of hla-b27 were expressed. the latter was termina ...19902150332
identification of bluetongue virus vp6 protein as a nucleic acid-binding protein and the localization of vp6 in virus-infected vertebrate cells.recently the insect baculovirus autographa californica nuclear polyhedrosis virus (acnpv) has been effectively adapted as a highly efficient vector in insect cells for the expression of various genes. a cdna sequence of rna segment 9 of bluetongue virus serotype 10 (btv-10, an orbivirus member of the reoviridae family) encoding a minor core protein (vp6) has been inserted into the bamhi site of the pacym1 transfer vector derived from acnpv. spodoptera frugiperda cells were cotransfected with the ...19902152806
identification of a viral gene encoding a ubiquitin-like protein.the baculovirus autographa californica nuclear polyhedrosis virus (acmnpv, which is representative of the mnpv subtype in which the virions may contain many nucleocapsids within a single viral envelope) encodes a protein, v-ubi, that has 76% identity with the eukaryotic protein ubiquitin. transcriptional mapping indicated that the gene for v-ubi was transcribed during the late phase of viral infection. two transcriptional start sites potentially encoding v-ubi were identified. both sites were co ...19902153300
sequence comparison of cellular and viral copies of host cell dna insertions found in autographa californica nuclear polyhedrosis virus.the nucleotide sequence and structural characteristics of two nonhomologous host dna insertions of spodoptera frugiperda (fall armyworm) origin isolated from few polyhedra mutants of the baculovirus autographa californica nuclear polyhedrosis virus (acmnpv) have been determined. neither of the host insertions contain long open reading frames suggesting that cellular genes were not introduced into the viral genome. one of the host dna insertions, ifp1.6, terminated in short imperfect inverted rep ...19902154879
purification and characterization of the recombinant extracellular domain of human nerve growth factor receptor expressed in a baculovirus system.to obtain the large quantities of the extracellular domain of the nerve growth factor receptor (ngf-r) necessary for structural analyses, we produced this protein in the baculovirus expression system. a cdna coding for the extracellular domain of the human ngf-r was first introduced into transfer vector pvl941. recombinant baculovirus was produced by cotransfecting spodoptera frugiperda cells with the transfer vector and dna of autographa californica nuclear polyhedrosis virus. recombinant viral ...19902155239
primary structure of the s peplomer gene of bovine coronavirus and surface expression in insect cells.the nucleotide sequence of the s peplomer gene of bovine coronavirus (bcv) has been determined. a single open reading frame of 4089 nucleotides encodes a polypeptide of 150k with 20 potential sites for addition of n-linked oligosaccharides. expression of the cloned bcv s gene by a recombinant of autographa californica nuclear polyhedrosis virus resulted in production of a 180k glycosylated polypeptide which was transported to the surface of the cell. comparison of the bcv s gene with the analogo ...19902155283
synthesis of bluetongue virus (btv) corelike particles by a recombinant baculovirus expressing the two major structural core proteins of btv.the l3 and m7 genes of bluetongue virus (btv), which encode the two major core proteins of the virus (vp3 and vp7, respectively), were inserted into a baculovirus dual-expression transfer vector and a recombinant baculovirus expressing both foreign genes isolated following in vivo recombination with wild-type autographa californica nuclear polyhedrosis virus dna. spodoptera frugiperda insect cells infected with the recombinant synthesized large amounts of btv corelike particles. these particles ...19902157041
an insertion of insect cell dna in the 81-map-unit segment of autographa californica nuclear polyhedrosis virus dna.in this report, a transposonlike insertion of spodoptera frugiperda insect cell dna was analyzed in single-plaque isolate e of the insect baculovirus autographa californica nuclear polyhedrosis virus (acnpv). the 634-base-pair insertion is characterized by an 18-base-pair terminal inverted repeat and carries an ecori site. this additional ecori site in the 81-map-unit segment of the dna of plaque isolate e of acnpv explains the difference between the ecori restriction map of the dna from this is ...19902157067
enzymatic activities of overexpressed herpes simplex virus dna polymerase purified from recombinant baculovirus-infected insect cells.biochemical characterization of the herpes simplex virus (hsv) dna polymerase, a model dna polymerase and an important target for antiviral drugs, has been limited by a lack of pure enzyme in sufficient quantity. to overcome this limitation, the hsv dna polymerase gene was introduced into the baculovirus, autographa californica nuclear polyhedrosis virus, under the control of the polyhedrin promoter to give rise to a recombinant baculovirus, bp58. bp58-infected spodoptera frugiperda insect cells ...19902157192
identification of epstein-barr virus terminal protein 1 (tp1) in extracts of four lymphoid cell lines, expression in insect cells, and detection of antibodies in human sera.the terminal proteins tp1 and tp2 are putative products of epstein-barr virus (ebv) genes expressed during the latent cycle of the virus. they are predicted to code for 53- and 40-kilodalton integral membrane proteins. we used the baculovirus autographa californica nuclear polyhedrosis virus as an expression vector to produce tp1 in large amounts in insect cells. the dna sequences used to express tp1 originated from a tp1 cdna derived from an m-aba/cbl1 cdna library. rabbit antisera raised again ...19902159542
high level expression of the two outer capsid proteins of bluetongue virus serotype 10: their relationship with the neutralization of virus infection.dna representing rna segments 2 and 5 of bluetongue virus (btv) serotype 10, corresponding to the genes that code for the outer capsid proteins vp2 and vp5, have been inserted into a baculovirus transfer vector in lieu of the coding region of the polyhedrin gene of autographa californica nuclear polyhedrosis virus (acnpv). after co-transfection of spodoptera frugiperda cells with wild-type acnpv dna in the presence of the recombinant transfer vector dnas polyhedrin-negative recombinant baculovir ...19902160763
construction of genetically engineered baculovirus insecticides containing the bacillus thuringiensis subsp. kurstaki hd-73 delta endotoxin.the delta-endotoxin gene from bacillus thuringiensis subsp. kurstaki hd-73 was inserted into autographa californica nuclear polyhedrosis virus (acmnpv) using two transfer vector systems. in the first, the delta-endotoxin gene was placed under the control of the polyhedrin gene promoter in lieu of the polyhedrin coding sequences, thus deriving a polyhedrin-negative virus. in the second, it was inserted under the control of a copy of the acmnpv p10 promoter positioned upstream of the polyhedrin ge ...19902165136
synthesis of foot-and-mouth disease virus capsid proteins in insect cells using baculovirus expression vectors.foot-and-mouth disease virus (fmdv) cdna cassettes containing sequences encoding the capsid precursor p1-2a with and without those encoding the proteases l and 3c were introduced into autographa californica nuclear polyhedrosis virus (acmnpv) expression vectors. procapsid proteins 1ab, 1c and 1d were produced in cells infected with recombinant baculoviruses, when l and 3c were present in the constructs, indicating that these fmdv proteases were active in insect cells. unlike p1 processing in pol ...19902167924
biophysical studies on the morphology of baculovirus-expressed bluetongue virus tubules.bluetongue virus tubules were purified from spodoptera frugiperda cells infected with a recombinant baculovirus containing the ns1 gene from bluetongue virus serotype 10, and expressed under control of the autographa californica nuclear polyhedrosis virus polyhedrin promoter. these tubules were subjected to a variety of chemical and physical treatments and the resulting effects on tubule morphology were examined by electron microscopy. a number of morphological similarities were noted between bl ...19902167940
synthesis of bluetongue virus-encoded phosphoprotein and formation of inclusion bodies by recombinant baculovirus in insect cells: it binds the single-stranded rna species.a dna clone of rna segment 8 (s8) of bluetongue virus type 10 (btv-10), an orbivirus member of the reoviridae family has been expressed to high levels (20 mg/1 x 10(9) cells) using an autographa californica nuclear polyhedrosis virus expression vector (pa-cym1). the expressed protein is similar to the authentic btv phosphoprotein ns2, in its size, antigenicity, and also the manner of phosphorylation (e.g. same peptides and residues). both mammalian and insect cell-derived ns2 proteins are phosph ...19902170574
expression of avian leukaemia virus env-gp85 in spodoptera frugiperda cells by use of a baculovirus expression vector.we studied the genetic expression of gp85 of avian leukaemia virus (alv) subgroup a in a baculovirus/insect cell system. 5'terminal sequences of the gag gene were added to precede the alv gp85 sequence and a stop codon was introduced at the boundary of gp85 and gp37. the resulting construct was then cloned into the baculovirus transfer vector pacym1, which contains the polyhedrin promoter of autographa californica nuclear polyhedrosis virus (acnpv). cells of the insect spodoptera frugiperda (sf9 ...19902174957
general analysis of receptor-mediated viral attachment to cell surfaces.viruses are multivalent particles that attach to cells through one or more bonds between viral attachment proteins (vap) and specific cellular receptors. three modes of virus binding are presented that can explain the diversity in binding data observed among viruses. they are based on multivalency of attachment and spatial versus receptor saturation effects which are easily distinguished based upon simple criteria. mode 1 involves only monovalent virus/receptor binding. modes 2 and 3 involve mul ...19902177356
the p6.5 gene region of a nuclear polyhedrosis virus of orgyia pseudotsugata: dna sequence and transcriptional analysis of four late genes.the gene encoding the basic dna-binding protein (p6.5) of the multicapsid nuclear polyhedrosis virus of orgyia pseudotsugata (opmnpv) was localized by southern blot analysis using a cdna probe containing the autographa californica virus (acmnpv) p6.9 gene. the opmnpv p6.5 gene was mapped to the hindiii g fragment at map unit 67. nucleotide sequence and transcriptional analysis of a 3.26 kb region encompassing this area revealed four open reading frames (orfs 1 to 4) oriented in the same directio ...19902179466
characterization of the basement membrane glycoprotein entactin synthesized in a baculovirus expression system.a cdna clone encoding the entire open reading frame of mouse entactin was constructed. this cdna was inserted into autographa californica multiple nuclear polyhedrosis virus and expressed in spodoptera frugiperda, sf9, insect cells. the recombinant entactin was produced in large quantities under the control of the polyhedrin promoter. amino terminus sequence analysis indicated that the signal peptide in the preprotein was correctly cleaved. polyclonal antibodies prepared against either the natur ...19902180961
expression and secretion of the bovine coronavirus hemagglutinin-esterase glycoprotein by insect cells infected with recombinant baculoviruses.a cdna fragment representing the hemagglutinin-esterase (he) gene of bovine coronavirus (bcv) was inserted into the genome of autographa californica nuclear polyhedrosis virus. infection of insect cells with the recombinant virus resulted in the production of a 120-kilodalton disulfide-linked dimeric form of the bcv he polypeptide. deletion of the carboxy-terminal hydrophobic domain from the he polypeptide resulted in secretion of a dimeric form of the truncated he polypeptide. the acetylesteras ...19902181154
expression of adenovirus type 2 dna polymerase in insect cells infected with a recombinant baculovirus.sequences encoding adenovirus type 2 dna polymerase were placed under control of the polyhedrin promoter and inserted into the baculovirus autographa californica nuclear polyhedrosis virus by homologous recombination. insect cells infected with the recombinant virus produced substantial amounts of the adenovirus type 2 dna polymerase protein which was functional in both dna polymerase and replication initiation reactions. thus, the baculovirus expression system can provide active adenovirus type ...19902181402
a capsid-associated protein of the multicapsid nuclear polyhedrosis virus of orgyia pseudotsugata: genetic location, sequence, transcriptional mapping, and immunocytochemical characterization.two lambda gt11 clones containing overlapping dna inserts encoding portions of a structural protein gene from orgyia pseudotsugata multicapsid nuclear polyhedrosis virus (opmnpv) were identified by their immunoreactivity with polyclonal antisera produced against purified polyhedra-derived virus. sequence analysis of a 3.6-kb region of the baculovirus genome (map units 69.1-71.6) from which the lambda gt11 inserts originated revealed an open reading frame of 1872 nt (624 amino acids) encoding a p ...19902184573
tissue-specific expression of silkmoth chorion genes in vivo using bombyx mori nuclear polyhedrosis virus as a transducing vector.a pair of silkmoth chorion chromosomal genes, hca.12-hcb.12, was inserted into a baculovirus transfer vector, pbmp2, derived from the nuclear polyhedrosis virus of bombyx mori. this vector, which permits the insertion of foreign genetic material in the vicinity of a mutationally inactivated polyhedrin gene, was used to acquire the corresponding recombinant virus. injection of mutant silkmoth pupae that lack all hc chorion genes with the recombinant virus resulted in the infection of all internal ...19902187186
antigenic parvovirus b19 coat proteins vp1 and vp2 produced in large quantities in a baculovirus expression system.two baculovirus expression vectors derived from autographica californica nuclear polyhedrosis virus (acnpv) were prepared containing the complete 2.5 kb coding region for parvovirus b19 coat protein vp1 (acb19vp1l) and the 1.8 kb coding region for vp2 (acb19vp2l), placed under the control of the polyhedrin promoter. the recombinant viruses were used to infect spodoptera frugiperda cells and the proteins expressed were analysed using appropriate antibodies. acb19vp1l-infected cells produced b19 v ...19902188463
characterization of the da26 gene in a hypervariable region of the autographa californica nuclear polyhedrosis virus genome.a region of the baculovirus autographa californica nuclear polyhedrosis virus genome that is frequently found to be altered after serial passage of the virus in cell culture was characterized. sequence analysis of this region of the genome in wild-type and mutant viruses revealed that some of the mutations affected a 675 bp open reading frame, designated da26. the da26 gene was disrupted both by deletion and by insertion of sequences that resembled transposable elements. northern blot analysis o ...19902189022
rabies diagnostic reagents prepared from a rabies n gene recombinant expressed in baculovirus.a gene encoding the nucleoprotein (n) of rabies virus was inserted into the genome of the baculovirus autographa californica nuclear polyhedrosis virus. recombinant gene expression was controlled by the strong polyhedrin gene promoter. insect cells (spodoptera frugiperda) infected by a baculovirus recombinant containing the rabies virus n gene produced abundant amounts of a novel 55-kilodalton protein of a size comparable to that of the rabies virus n protein, as demonstrated by polyacrylamide g ...19902191008
analysis of very late gene expression by autographa californica nuclear polyhedrosis virus and the further development of multiple expression vectors.the consequences of locating the polyhedrin gene coding sequences and the p10 promoter at heterologous positions within the autographa californica nuclear polyhedrosis virus (acmnpv) genome were investigated. positioning the polyhedrin or beta-galactosidase coding sequences under the control of the p10 gene promoter via the use of the new transfer vector, pacuw1, resulted in viable recombinant viruses able to produce high levels of each non-fused gene product at the appropriate time. polyhedra w ...19902197369
expression of influenza a and b virus nucleoprotein antigens in baculovirus.full-length cdna clones of the nucleoprotein (np) genes of influenza a/ann arbor/6/60 and b/ann arbor/1/86 viruses were constructed from virion rna and subsequently expressed in spodoptera frugiperda (sf9) cells using the baculovirus vector, autographa californica nuclear polyhedrosis virus. western blot analysis of lysates prepared from sf9 cells infected with the recombinant viruses confirmed that the baculovirus-expressed np antigens were reactive with monoclonal antibodies specific for eithe ...19902197370
functional expression of shaker k+ channels in a baculovirus-infected insect cell line.we constructed a recombinant baculovirus, a. californica nuclear polyhedrosis virus, containing the drosophila shaker h4 k+ channel cdna under control of the polyhedrin promoter. when infected with this recombinant baculovirus, the cell line sf9, derived from the army-worm caterpillar s. frugiperda, expresses fully functional shaker transient k+ currents, as assayed by whole-cell recording. k+ currents begin to appear at about 15 hr after infection, and they continue to increase over the next 3 ...19902200450
human acidic fibroblast growth factor overexpressed in insect cells is not secreted into the medium.we have overexpressed human acidic fibroblast growth factor (afgf) in spodoptera frugiperda sf9 cells from a cdna clone under the control of the promoter of the polyhedrin gene of the baculovirus autographa californica nuclear polyhedrosis virus. a 16.5-kd product was made in recombinant virus-infected cells that specifically reacted in immunoblots with various antibodies prepared against afgf. recombinant afgf was mitogenic for bhk21 cells and its activity was stimulated by heparin. the mechani ...19902200451
molecular cloning and physical mapping of the genome of bombyx mori nuclear polyhedrosis virus.a restriction fragment library which covered the entire genome of bombyx mori nuclear polyhedrosis virus (bmnpv) was constructed using plasmid vectors. by analysis of cloned and viral dna by double digestion with endonucleases and by hybridization techniques, a complete physical map of bmnpv was constructed for bamhi, ecori, hindiii, kpni, psti and smai. five regions of repeated sequences containing ecori sites were also found and mapped.19902202783
secretion of functional papain precursor from insect cells. requirement for n-glycosylation of the pro-region.the synthetic gene coding for the precursor of the cysteine protease papain (ec 3.4.22.2) has been expressed using the baculovirus/insect cell system. the prepropapain gene was cloned into the transfer vector ipdc125 behind the polyhedrin promoter. the recombinant construct was then incorporated by homologous recombination into the autographa californiaca nuclear polyhedrosis virus genome. the host spodoptera frugiperda sf9 cells infected with the recombinant baculovirus secrete an enzymatically ...19902204628
expression of the gene encoding firefly luciferase in insect cells using a baculovirus vector.a cdna encoding the firefly luciferase [photinus luciferin: oxygen 4-oxidoreductase (decarboxylating, atp-hydrolyzing), ec 1.13.12.7] was cloned downstream from the polyhedrin gene promoter of autographa californica nuclear polyhedrosis virus and expressed in spodoptera frugiperda clone-9 cells. synthesis of luciferase (luc) was accurately measured in insect cells growing in a 96-well plate, by a simple, rapid, nonradioactive, inexpensive and sensitive method based on fogging of x-ray film. luc ...19902205537
differential gene expression mediated by late, very late and hybrid baculovirus promoters.a series of recombinant viruses was constructed to study the regulation of expression from the promoter (pcap) for the major capsid-protein-encoding gene (vp39) of the baculovirus, autographa californica nuclear polyhedrosis virus. each virus of this series contains the cat reporter gene under the control of pcap or portions thereof. pcap regulation of cat was determined at the rna and enzyme activity levels, and was compared to cat gene expression driven by ppolh, the promoter of the polyhedrin ...19902205543
the expression of the autographa californica nuclear polyhedrosis virus genome in insect cells.this report presents a synopsis of recently published work in our laboratory on the molecular biology of the insect baculovirus autographa californica nuclear polyhedrosis virus (acnpv). the following studies have been summarized. (1) on the mode of transcription of the acnpv genome in insect cells. (2) translation of proteins encoded in the 81.2 to 85.0 map unit segment of acnpv. (3) inserts of insect cell dna in the acnpv genome. (4) expression of influenza (fowl plague) virus haemagglutinin i ...19902205973
expression and characterization of the chick nicotinic acetylcholine receptor alpha-subunit in insect cells using a baculovirus vector.a baculovirus transfer vector was constructed containing an entire cdna copy of the chick nicotinic acetylcholine receptor (nachr) alpha-subunit under control of the autographa californica nuclear polyhedrosis virus (acnpv) polyhedrin gene promoter. recombinant baculovirus was obtained by co-transfection of spodoptera frugiperda cells with infectious, wild-type acnpv dna and the transfer vector. polyhedrin-negative, recombinant viruses were identified which expressed the nachr alpha-subunit. the ...19902209600
linearization of baculovirus dna enhances the recovery of recombinant virus expression vectors.engineered derivatives of autographa californica multiple nucleocapsid nuclear polyhedrosis virus (acmnpv) possessing a unique restriction site provide a source of viral dna that can be linearized by digestion with a specific endonuclease. circular or linearized dna from two such viruses were compared in terms of their infectivity and recombinogenic activities. the linear forms were 15- to 150-fold less infectious than the corresponding circular forms, when transfected into spodoptera frugiperda ...19902216760
expression, characterization, and purification of a phosphorylated rabies nucleoprotein synthesized in insect cells by baculovirus vectors.a baculovirus expression vector (acnpv3) derived from the nuclear polyhedrosis virus of autographa californica (acnpv) was prepared containing the complete coding region of the nucleoprotein (n) gene of rabies virus (gif-sur-yvette clone of the cvs strain). the gene was placed under the control of the acnpv polyhedrin promoter and was expressed to high levels (66 mg n protein/liter of 2 x 10(9) cells) by the derived recombinant virus using a spodoptera frugiperda cell line. using available antis ...19902219704
nucleotide sequence and characterization of the 39k gene region of autographa californica nuclear polyhedrosis virus.the complete nucleotide sequence of the pstl-k fragment of the autographa californica nuclear polyhedrosis virus (acmnpv) genome was determined. this region of the genome contains the delayed early 39k gene and v-ubi, a viral protein with homology to ubiquitine. in addition, pstl-k potentially encodes five other proteins. hybrid-select translation mapped nine viral-specific proteins to this fragment. three proteins were observed with both early and late rna; two of them comigrated with proteins ...19902219715
expression of cauliflower mosaic virus gene i using a baculovirus vector based upon the p10 gene and a novel selection method.a new baculovirus expression vector based upon the p10 gene of autographa californica nuclear polyhedrosis virus (acnpv) and a novel system for the screening of p10 recombinants have been developed. the insertion of a cassette containing the lacz gene under the control of a heat-shock promoter of drosophila melanogaster downstream from the cloning site in p10 transfer vectors allows the convenient identification of putative recombinants by virtue of their expression of beta-galactosidase. using ...19902219726
expression of cauliflower mosaic virus gene i in insect cells using a novel polyhedrin-based baculovirus expression vector.an improved polyhedrin-based baculovirus expression vector was constructed to expedite distinguishing infections by putative baculovirus recombinants from infections by wild-type (wt) baculovirus. the vector utilizes the escherichia coli beta-galactosidase gene (lacz) as a genetic marker for positive recombination between wt autographa californica nuclear polyhedrosis virus and the baculovirus transfer vector. the marker gene/expression cassette was constructed so that lacz and the deleted polyh ...19902230725
[purification of autographa californica nuclear polyhedrosis virus dna and cloning of the polyhedrin gene].autographa califonica nuclear polyhedrosis virus (acnpv) dna from larvae of lepidopteran infected by acnpv has been isolated. the ecori fragments of acnpv dna have been cloned using plasmid pbr325 as a vector. the polyhedrin gene fragment containing recombinant plasmid pac-18 was isolated through in situ hybridization. for the convenience of further construction the ecori insertion fragment was cloned into puc-8. thus plasmid puac-2 was obtained. the results of restriction mapping of pac-18 and ...19902242284
identification and characterization of a baculovirus occlusion body glycoprotein which resembles spheroidin, an entomopoxvirus protein.a 37-kda polypeptide specified by autographa californica nuclear polyhedrosis virus was found to share significant homology with choristoneura biennis entomopoxyvirus spheroidin protein, which is the major component of entomopoxvirus occlusion bodies. antibodies raised against spheroidin cross-reacted with the 37-kda protein and confirmed its expression in the late phase of wild-type baculovirus infection. immunoblot analysis and fluorescence microscopy demonstrated that the protein was associat ...19902243377
infected cell specific protein and viral dna synthesis in productive and abortive infections of spodoptera frugiperda nuclear polyhedrosis virus.this study examines viral protein and dna synthesis in spodoptera frugiperda multicapsid nuclear polyhedrosis virus (sfmnpv) infections of s. frugiperda and trichoplusia ni cells. a total of 28 infected cell specific polypeptides (icsps) were detected in the productive s. frugiperda cells. of these, 14 were identified as structural polypeptides. based on the change in their rate of synthesis during the replication cycle, these icsps were grouped into four classes. only a 97k and a 29k icsp were ...19902248550
expression of plant virus genes in animal cells: high-level synthesis of cowpea mosaic virus b-rna-encoded proteins with baculovirus expression vectors.the baculovirus expression system has been used to produce non-structural proteins encoded by bottom-component rna (b-rna) of cowpea mosaic virus (cpmv). for this, cdnas containing the 60k, 87k, 110k and 170k protein coding sequences were each provided with an atg start codon and the cdna containing the 60k coding sequence with a taa stop codon immediately downstream of the coding sequence. recombinant baculoviruses were retrieved which harboured the modified b-cdna sequences under the control o ...19902254749
characteristically distinct isolates of the nuclear polyhedrosis virus from spodoptera litura.more than 100 isolates were plaque-purified to examine the genetic variations in four wild stocks of spodoptera litura nuclear polyhedrosis virus (npv) collected in japan. these isolates were characterized by their in vitro host range in three established insect cell lines, growth characteristics, polyhedral protein, dna restriction endonuclease pattern and dna hybridization. the isolates were separated into four distinct groups: (i) isolates corresponding to autographa californica npv, (ii and ...19902254753
characterization of the infection cycle of the orgyia pseudotsugata multicapsid nuclear polyhedrosis virus in lymantria dispar cells.to characterize the infection cycle of the orgyia pseudotsugata multicapsid nuclear polyhedrosis virus in lymantria dispar cells, the time course of dna synthesis and polyhedron production, and the onset and rate of budded virus production were investigated at three different m.o.i. (5, 10 and 100). in addition, the time course of expression of three proteins (gp64, p39 and polyhedrin) representative of three temporal classes of baculovirus genes was also analysed using western blot analysis. dn ...19902273385
nucleotide sequence and transcriptional analysis of the hindiii p region of a temperature-sensitive mutant of autographa californica nuclear polyhedrosis virus.dna sequence analysis of the hindiii p region of a temperature-sensitive mutant of autographa californica nuclear polyhedrosis virus confirmed the specific amplification of 1.4 kb of viral dna from this region of the genome. the sequenced region included an open reading frame, translated in a counterclockwise direction, which would potentially encode a 74k protein. the amplified dna was contained within this open reading frame, resulting in in-frame amplifications of a domain within the protein. ...19902273394
nucleotide sequence of a circular single-stranded dna associated with coconut foliar decay virus.a circular single-stranded (ss) covalently closed (ccc) dna associated with coconut foliar decay virus (cfdv) was purified, amplified by the polymerase chain reaction, and subcloned and its sequence established by analysis of overlapping subgenomic cdna clones. the complete cfdv sequence comprised 1291 nucleotides and contained open reading frames for six proteins of molecular weight larger than 5 kda. one of these (orf1, 33.4 kda) codes for a leucine-rich protein with the nucleoside triphosphat ...19902345968
expression of human granulocyte-macrophage colony-stimulating factor gene in insect cells by a baculovirus vector.a plasmid pac373gm-csf was constructed and co-transfected into spodoptera frugiperda (sf9) cells with wild-type autographa californica nuclear polyhedrosis virus (acnpv) dna. the recombinant virus vac373gm-csf was identified and purified by several rounds of plaque hybridization. by assaying the culture medium, we demonstrated recombinant virus infected sf9 cells expressing hgm-csf. recombinant hgm-csfs with apparent molecular masses of 14.5, 15.5 and 16.5 kda were detected by the western blot m ...19902403525
a baculovirus polyhedron envelope protein: immunogold localization in infected cells and mature polyhedra.a polyclonal antiserum against a trpe fusion protein containing the complete open reading frame of the polyhedron envelope (pe) protein from the nuclear polyhedrosis virus of orgyia pseudotsugata (opmnpv) was used for immunogold staining and electron microscopic examination of polyhedra, isolated polyhedron envelopes, and infected insect cells at selected times postinfection. the antiserum specifically stained the peripheral envelope of mature polyhedra and also stained the envelope structure wh ...19902403704
identification of virus-specific polypeptides and translatable mrnas in the isolated pupal abdomens of the silkworm, bombyx mori, infected with nuclear polyhedrosis virus.analysis by sodium dodecyl sulfate-polyacrylamide gel electrophoresis demonstrated that infection of the isolated pupal abdomens of the silkworm, bombyx mori, with b. mori nuclear polyhedrosis virus (bmnpv) caused generation of a number of polypeptides with a concomitant decrease of cellular polypeptides. these generated polypeptides were not identified as viral structural polypeptides, but were characterized as the degradation products of cellular polypeptides, as evidenced by the reaction with ...19902405063
rate of increase of autographa californica nuclear polyhedrosis virus in trichoplusia ni larvae determined by dna:dna hybridization.the rate of increase and doubling time of the hob clone of autographa californica nuclear polyhedrosis virus (acmnpv-hob) in neonate trichoplusia ni larvae was determined by measuring the increase in viral dna through time following inoculation with average doses of 50 or 17,400 occlusion bodies per larva. changes in total dna and viral dna through time were followed by fluorescence spectroscopy and quantitative slot-blot dna:dna hybridization, respectively. total dna content (i.e., larval dna a ...19902405064
structure of preproattacin and its processing in insect cells infected with a recombinant baculovirus.from a cdna library made from fatbody of immunized hyalophora cecropia pupae, a full-length clone corresponding to basic attacin was isolated. the corresponding amino acid sequence suggests that basic attacin is synthesized as a 233-residue preproprotein. this was confirmed by cloning the cdna fragment encoding the basic attacin in the baculovirus autographa californica nuclear polyhedrosis virus downstream of the polyhedrin promoter and expressing the protein in spodoptera frugiperda (sf9) cell ...19902406140
expression of the lassa virus nucleocapsid protein in insect cells infected with a recombinant baculovirus: application to diagnostic assays for lassa virus infection.the coding region of the gene for the nucleocapsid protein of lassa virus has been inserted into the genome of autographa californica nuclear polyhedrosis virus (acnpv) using the transfer vector pacym1, so that expression of the foreign dna is under the control of the promoter of the acnpv polyhedrin gene. infection of cultured spodoptera frugiperda cells with recombinant virus resulted in the synthesis of high levels of a protein that was indistinguishable from the authentic lassa virus protein ...19902406367
overlapping divergent transcripts mapping to the hindiii f region of the autographa californica nuclear polyhedrosis virus.we have mapped a set of transcripts that cross the xhoi site in the hindiii f fragment of the genome of the autographa californica nuclear polyhedrosis virus. these transcripts overlap at their 5' ends by about 550 bases and run in opposite directions. we have tentatively identified two open reading frames corresponding to the leftward transcript. the rightward transcript is present from 8 h post-infection (p.i.) to 24 h p.i.; the leftward transcripts are present from 2 h p.i. to 24 h p.i. the e ...19902406368
functional analysis of a 603 nucleotide open reading frame upstream of the polyhedrin gene of autographa californica nuclear polyhedrosis virus.the sequence of the 2000 nucleotides immediately upstream of the polyhedrin gene of the autographa californica multiple nucleocapsid nuclear polyhedrosis virus has been determined. comparative analysis of the data identified a 603 nucleotide open reading frame (orf) separated from the polyhedrin gene coding sequences by 156 nucleotides and in the opposite strand of dna. northern hybridization analysis of polyadenylated rna from infected cells highlighted a 3.7 kb species produced maximally at 12 ...19902407804
autographa californica m nuclear polyhedrosis virus: microtubules and replication.progressive reorganization and depolymerization of microtubules corresponded with virus-induced rounding of autographa californica m nuclear polyhedrosis virus (acmnpv)-infected spodoptera frugiperda iplb-sf-21 cells, suggesting that microtubules were instrumental in maintaining the normal shape of these cells. depolymerization of all cortical and most of the paranuclear microtubules with colchicine also resulted in cell rounding, confirming this hypothesis. studies with aphidicolin and cyclohex ...19902408230
isolation of temperature sensitive mutants of autographa californica nuclear polyhedrosis virus: phenotype characterization of baculovirus mutants defective in very late gene expression.temperature sensitive mutants of autographa californica nuclear polyhedrosis virus were isolated following exposure of parental replicating virus to 5-bromo-2'-deoxyuridine. two mutants designated ts317 and ts538 were characterized in detail. both mutants synthesized viral dna but were defective in infectious extracellular virus production at the nonpermissive temperature suggesting defects in late gene regulation. pulse-labeling experiments indicated that a switch to late protein synthesis occu ...19902408231
continuous production of baculovirus in a cascade of insect-cell reactors.insect cells (spodoptera frugiperda) were cultured in a continuous stirred-tank reactor. the effluent was led to a cascade of another two reactors, each containing half the volume of the cell-growth reactor, where the cells were infected with autographa californica nuclear polyhedrosis virus. for about 10 days production of 10(7) polyhedra (virus particles embedded in a protein capsule) per cm3 was achieved. this short production time compared to previous experiments involving an analogous syste ...19901366563
multistage production of autographa californica nuclear polyhedrosis virus in insect cell cultures.the aim of our study was to establish an efficient system for the in vitro production of the insect pathogenic autographa californica nuclear polyhedrosis virus in a spodoptera frugiperda cell line. we optimized cultivation conditions for cell proliferation as well as for virus replication in a 1.5 litre stirred tank bioreactor. cell and virus propagation were found to be optimal at a constant oxygen tension of 40%. in order to provide sufficient nutrients during virus synthesis filtration and p ...19901366992
dna distribution and respiratory activity of spodoptera frugiperda populations infected with wild-type and recombinant autographa californica nuclear polyhedrosis virus.spodoptera frugiperda cells were infected with a wild-type autographa californica nuclear polyhedrosis virus and with a recombinant autographa californica nuclear polyhedrosis virus. the recombinant virus was derived from the wild-type virus and produced beta-galactosidase instead of polyhedrin. the changes in cell size, cell growth, viability, dna distribution, and respiratory activity were followed through the time course of the infection. the dna content as measured by flow cytometry of infec ...19901367465
simulated acid rain reduces the susceptibility of the european pine sawfly (neodiprion sertifer) to its nuclear polyhedrosis virus.the study dealt with the effect of simulated acid rain (both h(2)so(4) and hno(3); acidities of ph 4 and ph 3) on the susceptibility of the larvae of neodiprion sertifer to its nuclear polyhedrosis virus. scots pines growing in a subarctic area with low ambient pollution levels were irrigated with simulated acid rain during two summers. neodiprion larvae fed with foliage from the experimental trees were infected with a dilute virus suspension. the acid treatment of host trees had a significant e ...199022160113
risk assessment studies: detailed host range testing of wild-type cabbage moth, mamestra brassicae (lepidoptera: noctuidae), nuclear polyhedrosis virus.the host range of a multiply enveloped nuclear polyhedrosis virus (npv) (baculoviridae) isolated from the cabbage moth, mamestra brassicae (lepidoptera: noctuidae), was determined by challenging a wide range of insect species with high (10 polyhedral inclusion bodies) and low (10 polyhedral inclusion bodies) doses of the virus. the identity of the progeny virus was confirmed by dot blotting. analysis of 50% lethal dose was carried out on selected species, and the progeny virus was identified by ...199016348279
insecticidal activity of a bacterial crystal protein expressed by a recombinant baculovirus in insect cells.baculoviruses are insect pathogens with a relatively slow speed of action, and this has limited their use as control agents of insect pests. introduction into baculoviruses of genes which code for proteins interfering specifically with insect metabolism or metamorphosis, such as toxins, hormones, and enzymes, may enhance the pathogenicity of these viruses. the complete insecticidal crystal protein gene cryia(b) of bacillus thuringiensis subsp. aizawai 7.21 was engineered into the nuclear polyhed ...199016348284
co-occlusion and persistence of a baculovirus mutant lacking the polyhedrin gene.a co-occlusion process was evaluated as a commercially and ecologically acceptable strategy for the development of genetically improved baculovirus insecticides. coinfection of spodoptera frugiperda (iplb-sf-21) tissue culture cells with autographa californica nuclear polyhedrosis virus (acmnpv) and an acmnpv mutant (ac-e10) lacking the polyhedrin gene resulted in occlusion of both virus types within polyhedra. the amount of occluded ac-e10 virions in progeny polyhedra populations during serial ...199016348313
comparative replication of lymantria dispar nuclear polyhedrosis virus strains in three continuous-culture cell lines.we compared the replication of the gypsy moth (lymantria dispar) nuclear polyhedrosis virus in two new cell lines, from embryos and fat body of l. dispar, and in a previously available ovarian cell line. three virus isolates (the hamden strain [ldp-67] used commercially as gypchek, a plaque-purified clone of hamden [5-7d], and an isolate from abington, mass. [ab]) were each tested on the three cell lines. the fat-body-derived cell line proved best in terms of occlusion body production for all th ...198916347901
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 ...198918588202
high level expression of nonfused foreign genes with autographa californica nuclear polyhedrosis virus expression vectors.high levels of nonfused chloramphenicol acetyltransferase, beta-galactosidase, and beta-glucuronidase expressed under the control of new vector constructs of the polyhedrin promoter in spodoptera frugiperda cells infected with autographa californica nuclear polyhedrosis virus were investigated by sds-page and rna dot blot analysis of total cytoplasmic rna. when the polyhedrin atg start codon was converted to att by site-directed mutagenesis, translation initiated at downstream atg codons resulti ...19892497580
a baculovirus blocks insect molting by producing ecdysteroid udp-glucosyl transferase.the predicted amino acid sequence of a newly identified gene of the insect baculovirus autographa californica nuclear polyhedrosis virus was similar to several uridine 5'-diphosphate (udp)-glucuronosyl transferases and at least one udp-glucosyl transferase. genetic and biochemical studies confirmed that this gene encodes an ecdysteroid udp-glucosyl transferase (egt). this enzyme catalyzes the transfer of glucose from udp-glucose to ecdysteroids, which are insect molting hormones. expression of t ...19892505387
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