Publications

TitleAbstractYear(sorted ascending)
Filter
PMID
Filter
identification and characterization of the ecdysteroid udp-glucosyltransferase gene of the lymantria dispar multinucleocapsid nuclear polyhedrosis virus.we have located, cloned, sequenced and characterized the ecdysteroid udp-glycosyltransferase gene (egt) gene from the baculovirus lymantria dispar multinucleocapsid nuclear polyhedrosis virus. (ldmnpv), which is specific for the gypsy moth (l. dispar). the egt gene from the related baculovirus autographa californica multinucleocapsid nuclear polyhedrosis virus (acmnpv) disrupts the hormonal balance of the host larva by galactosylating ecdysone, which prevents moulting. the location of the ldmnpv ...19948151299
high-level expression and purification of secreted forms of herpes simplex virus type 1 glycoprotein gd synthesized by baculovirus-infected insect cells.two forms of herpes simplex virus glycoprotein gd were recombined into autographa californica nuclear polyhedrosis virus (baculovirus) and expressed in infected spodoptera frugiperda (sf9) cells. each protein was truncated at residue 306 of mature gd. one form, gd-1(306t), contains the coding sequence of patton strain herpes simplex virus type 1 gd; the other, gd-1(qaat), contains three mutations which eliminate all signals for addition of n-linked oligosaccharides. prior to recombination, each ...19948289380
the insect tracheal system: a conduit for the systemic spread of autographa californica m nuclear polyhedrosis virus.baculoviruses establish systemic infections within susceptible insect hosts, even though host tissues are surrounded by basal laminae, extracellular matrices that exclude particles smaller than these viruses. using a recombinant autographa californica m nuclear polyhedrosis virus containing a lacz reporter gene under the control of a constitutive promoter, we followed the progression of infection in trichoplusia ni larvae. we discovered that infection of the larval insect tracheal system (and no ...19948159729
functional dissection of the ie2 gene product of the baculovirus autographa californica nuclear polyhedrosis virus.the psti-n genomic fragment of autographa californica nuclear polyhedrosis virus (acnpv) encodes an immediate-early protein, ie2, that functions as a promiscuous transactivator of other early viral promoters and heterologous promoters both in vivo and in vitro. ie2 contains several sequence motifs that are common to transcriptional activators. we have employed site-directed mutagenesis coupled with transient-expression assays to identify the amino acid sequences of ie2 that are essential for tra ...19948009830
autographa californica nuclear polyhedrosis virus, pdv, and ecv viral envelopes and nucleocapsids: structural proteins, antigens, lipid and fatty acid profiles.autographa californica nuclear polyhedrosis virus (acmnpv) infection results in the production of two types of infectious, enveloped viruses. as both of these viral forms play significantly different roles in the virus life cycle, the different functional characteristics in the roles of the virus may be explained, in part, by the protein and lipid composition and source of the viral envelopes. both viruses utilize different maturation and envelopment strategies: extracellular virus (ecv) obtains ...19948009843
engineering the assembly pathway of the baculovirus-insect cell expression system.the synthesis of complex biological structures such as antibodies using recombinant dna technology is a major biotechnological advance. active murine antibody (igg) oligomers, composed of two heavy (h) and two light (l) polypeptide chains, have been expressed and secreted by the baculovirus-insect cell expression system. unfortunately, expression of the functional antibodies is accompanied by the formation of abnormal protein complexes and aggregates in which the polypeptide chains are bound tog ...19948010671
expression of aleutian mink disease parvovirus capsid proteins in a baculovirus expression system for potential diagnostic use.a 2.3-kb cdna clone encoding aleutian mink disease parvovirus (adv) structural proteins vp1 and vp2 was inserted into the polyhedron gene of autographa californica nuclear polyhedrosis virus (acnpv) and expressed by the recombinant virus, acadv-1, in spodoptera frugiperda-9 cells. sodium dodecyl sulfate-polyacrylamide gel electrophoresis and western immunoblot analysis (wia) indicated that synthesis of both vp1 and vp2 was being directed by acadv-1. fluorescence microscopic examination of acadv- ...19948011776
superior expression of juvenile hormone esterase and beta-galactosidase from the basic protein promoter of autographa californica nuclear polyhedrosis virus compared to the p10 protein and polyhedrin promoters.the expression characteristics of the p10, polyhedrin and basic protein promoters of autographa californica nuclear polyhedrosis virus were compared using two reporter enzymes, juvenile hormone esterase (jhe) and beta-galactosidase. in these systems, jhe is exported from the cell and beta-galactosidase is localized to the cytosol. expression of jhe from the basic, p10 and polyhedrin promoters was first detected in the medium at 13, 19 and 27 h post-infection respectively. the basic protein promo ...19948021586
identification of the gp67 gene of a baculovirus pathogenic to the spruce budworm, choristoneura fumiferana multinucleocapsid nuclear polyhedrosis virus.the baculovirus gp67 gene encodes a ph-dependent membrane fusion protein and has been identified in both autographa californica multinucleocapsid nuclear polyhedrosis virus (acmnpv) and orygia pseudotsugata mnpv (opmnpv). we have identified a homologous gene in the spruce budworm virus, choristoneura fumiferana mnpv (cfmnpv). the cfmnpv gp67 gene is 79% identical to acmnpv gp67 at the level of nucleotide sequence and 82% identical at the level of predicted amino acid sequence. as with opmnpv and ...19948021612
functional dissection of the autographa california nuclear polyhedrosis virus enhancer element hr5.the hr5 enhancer element of autographa californica nuclear polyhedrosis virus stimulates transcription from baculovirus-delayed early promoters in the presence of the viral transactivator, ie1. gel retardation analyses of interactions between a fragment of hr5 and extracts prepared from cells transfected with an ie1-encoding plasmid revealed the presence of three dna-protein complexes. in order to better define the functional domains of the hr5 enhancer, we constructed a set of plasmids containi ...19948178424
genome organization of the dna-binding protein gene region of cryptophlebia leucotreta granulosis virus is closely related to that of nuclear polyhedrosis viruses.the nucleotide sequence and genomic organization of a conserved genome region within the ecori g fragment of cryptophlebia leucotreta granulosis virus (clgv) is presented. five open reading frames (orfs) were identified which were homologous to those of autographa californica nuclear polyhedrosis virus (acmnpv), located upstream of the helicase gene (p143) at 63.6 to 65.6 map units. the orfs of clgv and acmnpv share nucleotide sequence homologies of about 47 to 53% and are very similarly arrange ...19948021613
specificity of baculovirus p10 functions.three functional domains in baculovirus p10 proteins have been postulated for aggregation, nuclear disintegration, and fibrillar structure formation (van oers et al., j. gen. virol. 74, 563-574, 1993). to study the specificity of these functions, a recombinant autographa californica nuclear polyhedrosis virus (accr1) was constructed in which the coding sequence of the p10 gene was replaced with the p10 sequence of the distantly related spodoptera exigua (se) mnpv. in accr1-infected cells the sem ...19948178439
the complete dna sequence of autographa californica nuclear polyhedrosis virus.the complete nucleotide sequence of the genome of clone 6 of the baculovirus autographa californica nuclear polyhedrosis virus (acnpv) has been determined. the molecule comprises 133,894 base pairs and has an overall a + t content of 59%. our analysis suggests that the virus encodes some 154 methionine-initiated, and potentially expressed, open reading frames (orfs) of 150 nucleotides or greater. these orfs are distributed evenly throughout the virus genome on either strand. the orfs are arrange ...19948030224
[physical mapping of the bombyx mori nuclear polyhedrosis virus genome].the restriction map of the nuclear polyhedrosis dna virus of bombyx mori has been determined with the use of four restriction endonucleases: noti, bamhi, smai and kpni. 18 cleavage sites have been localized on the viral dna. total length of the viral dna is about 130 kb. the fragment containing a polyhedrin gene has been localized on the map by the blot hybridization technique.19948183306
control of programmed cell death by the baculovirus genes p35 and iap.the sf-21 insect cell line undergoes rapid and widespread apoptosis when treated with actinomycin d or when infected with a mutant of the baculovirus autographa californica nuclear polyhedrosis virus lacking a p35 gene or a functionally active iap (inhibitor of apoptosis) gene. here we provide evidence that the basis for the induction of apoptosis by these two different stimuli is the cessation of rna synthesis. we also show that expression of either p35 or two different functional iap homologs ...19948035800
characterization of glycosylated and catalytically active recombinant human alpha-galactosidase a using a baculovirus vector.fabry disease is an x-linked inborn error of glycolipid metabolism caused by a deficiency of the lysosomal enzyme alpha-galactosidase a (gala; ec 3.2.1.22). in order to obtain large quantities of this human enzyme for physical characterization and for the development of new approaches for enzyme therapy, we constructed derivatives of the autographa californica nuclear polyhedrosis virus that produce the human enzyme. the recombinant gala (re-gala) is produced at high levels, and is active with b ...19948039705
cloning and expression of bovine and porcine interleukin-2 in baculovirus and analysis of species cross-reactivity.the cdnas encoding bovine and porcine interleukin-2 (il-2) have been expressed using the baculovirus autographa californica nuclear polyhedrosis virus as a vector in insect cells. insect cells infected with recombinant viruses secreted bovine and porcine il-2 into the culture medium, with biological activities for maintaining the proliferation of homologous cells. when the activities of these two il-2 proteins and commercially available human il-2 were tested on heterologous cells differences we ...19948042283
nucleotide sequence of the polyhedrin gene of spodoptera littoralis multiple nucleocapsid nuclear polyhedrosis virus.1286 nt portion of the 3.1 kbp hindiii-k fragment of the spodoptera littoralis multiple nucleocapsid nuclear polyhedrosis virus (simnpv) dna genome has been sequenced. the sequence contains the polyhedrin gene preceded by a highly-repeated agataa-rich sequence. with 249 amino acids, simnpv polyhedrin is the longest known polyhedrin.19948049274
expression and characterization of human bone morphogenetic protein-2 in silkworm larvae infected with recombinant bombyx mori nuclear polyhedrosis virus.recombinant human bone morphogenetic protein-2 (rhbmp-2) was expressed in silkworm larvae, and a milligram quantity of the protein was purified and characterized. the expressed rhbmp-2 was biologically active in terms of induction of alkaline phosphatase activity in mc3t3-e1 cells and ectopic bone formation in mice. on sds-polyacrylamide gel electrophoretic analysis, the purified protein showed a 16 kda band under reducing conditions and a 30 kda band under non-reducing conditions. the silkworm- ...19948206877
a cysteine protease encoded by the baculovirus bombyx mori nuclear polyhedrosis virus.sequence analysis of the bamhi f fragment of the genome of bombyx mori nuclear polyhedrosis virus (bmnpv) revealed an open reading frame whose deduced amino acid sequence had homology to those of cysteine proteases of the papain superfamily. the putative cysteine protease sequence (bmnpv-cp) was 323 amino acids long and showed 35% identity to a cysteine proteinase precursor from trypanosoma brucei. of 36 residues conserved among cathepsins b, h, l, and s and papain, 31 were identical in bmnpv-cp ...19948083997
identification of three late expression factor genes within the 33.8- to 43.4-map-unit region of autographa californica nuclear polyhedrosis virus.a transient transactivation assay system was used in combination with an overlapping autographa californica nuclear polyhedrosis virus clone library to identify genes involved in late and very late baculovirus gene expression. we have identified three genes within the 33.8- to 43.4-map-unit region of the a. californica nuclear polyhedrosis virus genome which contribute to expression from promoters of the vp39 major capsid protein and polyhedrin genes. one of these three genes corresponds to the ...19948084003
a baculovirus gene involved in late gene expression predicts a large polypeptide with a conserved motif of rna polymerases.we have identified and sequenced a novel baculovirus gene, late expression factor eight gene (lef-8), of autographa californica nuclear polyhedrosis virus that is necessary for efficient expression from late and very late virus gene promoters in a transient expression assay. the predicted gene product, lef-8, has a molecular mass of 102 kda and contains a conserved sequence motif, gxkx4hgq/nkg, found in dna-directed rna polymerases throughout the animal, plant, and microbial kingdoms.19948207843
nucleotide sequence and genetic organization of a 7.3 kb region (map unit 47 to 52.5) of autographa californica nuclear polyhedrosis virus fragment ecori-c.the nucleotide sequence and genetic organization of a 7297 bp region within the ecori-c fragment of autographa californica multiple nucleocapsid nuclear polyhedrosis virus (acmnpv) are presented. eight putative open reading frames were found and their respective amino acid sequences compared with a number of data libraries. orf 1227 corresponded with gp41 and its predicted protein sequence was found to be 55 amino acids longer at its c terminus than reported previously. moreover the main part of ...19948126447
metallopanstimulin gene product produced in a baculovirus expression system is a nuclear phosphoprotein that binds to dna.the protein product of the human metallopanstimulin (mps-1) gene was produced in the insect cell line spodoptera frugiperda (sf9) using the baculovirus expression vector system autographa californica nuclear polyhedrosis virus (acnpv). when a cloned mps-1 complementary dna sequence was inserted into the acnpv viral genome downstream from the promoter of the polyhedrin gene, a polypeptide with an apparent molecular weight of approximately 10,000 was observed in extracts of infected sf9 cells. thi ...19947986747
a putative non-hr origin of dna replication in the hindiii-k fragment of autographa californica multiple nucleocapsid nuclear polyhedrosis virus.in addition to the seven known homologous regions (hrs) of autographa californica multiple nucleocapsid polyhedrosis virus (acmnpv) the hindiii-k fragment was also found to carry a putative ori, although this fragment does not contain an hr. deletion analysis showed that this ori contains several segments essential for its activity and other 'auxiliary' sequences that enhance the ori activity. sequence analysis identified several structures often found in other viral replication oris, such as pa ...19947996129
the granulin gene region of cryptophlebia leucotreta granulosis virus: sequence analysis and phylogenetic considerations.the nucleotide sequence of a 2.2 kb genome region of the baculovirus cryptophlebia leucotreta granulosis virus (cigv) encompassing the granulin gene and a second open reading frame, designated orf909, was determined. the putative granulin orf comprises 744 nucleotides encoding a polypeptide with a predicted m(r) of 29.3 k. the 5' leader of the granulin gene contains a canonical late baculovirus promoter (ataag) and differs only in two nucleotide positions from the sequence of cydia pomonella gra ...19947996162
human 17 beta-hydroxysteroid dehydrogenase: overproduction using a baculovirus expression system and characterization.estrogenic 17 beta-hydroxysteroid dehydrogenase (17 beta-hsd) plays a pivotal role in the synthesis of estrogens. we overproduced human placental estrogenic 17 beta-hsd using a baculovirus expression system for the study of the enzyme mechanism. a cdna encoding the entire open reading frame of human 17 beta-hsd was inserted into the genome of autographa californica nuclear polyhedrosis virus and expressed in spodoptera frugiperda (sf9) insect cells. metabolic labeling and western blot analysis u ...19947918113
interaction of trichoplusia ni granulosis virus-encoded enhancin with the midgut epithelium and peritrophic membrane of four lepidopteran insects.enhancin, an infectivity-enhancing protein from trichoplusia ni granulosis virus (tngv) was tested for its ability to increase autographa californica multiple nucleocapsid nuclear polyhedrosis virus (acmnpv) infection in the larvae of four lepidopteran insects. enhancin increased the mortality of acmnpv infection in all the four insect species tested. peritrophic membrane (pm) assays showed altered protein profiles in pms treated with enhancin in all the four species. this supports the hypothesi ...19948046398
the p10 gene of natural isolates of bombyx mori nuclear polyhedrosis virus encodes a truncated protein with an m(r) of 7700.sequence analysis of the p10 genes of three bombyx mori nuclear polyhedrosis virus (bmnpv) isolates collected in taiwan (ta) and japan (t3 and d1) showed that all possessed a deletion of an adenine residue, 210 bp downstream from the first base of the initiation codon when compared to the p10 gene of autographa californica (multinucleocapsid) npv (acmnpv). this deletion caused a downstream termination codon to come inframe with the coding sequence of p10, so that the p10 gene of bmnpv encoded a ...19948046414
expression of semliki forest virus nsp1-specific methyltransferase in insect cells and in escherichia coli.we have expressed the semliki forest virus (sfv)-specific nonstructural protein nsp1 both in insect cells and in escherichia coli in the absence of other viral proteins. a substantial amount of nsp1 was synthesized in sf9 cells infected with the recombinant autographa californica nuclear polyhedrosis virus (acnpv) acnpv-nsp1. these cells had a high level of guanine-7-methyltransferase activity compared with that of wild-type acnpv-infected cells. the methyltransferase activity and nsp1 were most ...19947933125
direct cloning into the autographa californica nuclear polyhedrosis virus for generation of recombinant baculoviruses. 19948052541
[primary structure of polyhedrin from the nuclear polyhedrosis virus of the silkworm malacosoma neustria]. 19948053947
subcore- and core-like particles of broadhaven virus (brdv), a tick-borne orbivirus, synthesized from baculovirus expressed vp2 and vp7, the major core proteins of brdv.the genes encoding the two major core proteins (vp2 and vp7) of broadhaven (brd) virus, a tick-borne orbivirus, were inserted into the genome of autographa californica nuclear polyhedrosis virus (acnpv) under the control of copies of the acnpv polyhedrin promoter to produce two recombinant baculoviruses. infection of spodoptera frugiperda (sf) cells with a recombinant acnpv that synthesized brdv vp2 produced large numbers of brdv subcore-like particles. co-infection of cells with the two recombi ...19948079519
overexpression, purification, and characterization of third component of complement.the third component of complement (c3) plays a critical role in both pathways of complement activation by interacting with numerous other complement proteins. to elucidate the molecular features of c3 that relate to the functional activities of the molecule, we expressed the cdna of human complement component c3 in cultured insect cells using a baculovirus expression vector system derived from the baculovirus autographa california nuclear polyhedrosis virus (acnpv). the expression of c3 was cont ...19947963591
the pk-1 gene of autographa californica multinucleocapsid nuclear polyhedrosis virus encodes a protein kinase.open reading frame (orf) 9 of the ecori i fragment of the baculovirus autographa californica multinucleocapsid nuclear polyhedrosis virus (acmnpv) genome encodes a protein, pk-1, which has strong similarity to serine-threonine protein kinases. the published sequence of the pk-1 gene contains an error that, when corrected, extends the orf by 228 nucleotides. transcription of pk-1 was first detectable by primer extension at 12 h post-infection, accumulating to high levels during the very late phas ...19947964609
nucleotide sequence of the polyhedrin gene region of helicoverpa zea single nucleocapsid nuclear polyhedrosis virus: placement of the virus in lepidopteran nuclear polyhedrosis virus group ii.the polyhedrin gene (polh) of helicoverpa zea single nucleocapsid nuclear polyhedrosis virus (hzsnpv) was identified and shown by sequence analysis of the ecori i genomic fragment to encode a 246 amino acid polypeptide that has greater than 80% sequence identity to known polyhedrins. it is preceded by an at-rich region containing the conserved late promoter motif taag, which was identified as a transcription start point. downstream of polh there were several similarities in genome arrangement to ...19947964631
suppression of apoptosis in insect cells stably transfected with baculovirus p35: dominant interference by n-terminal sequences p35(1-76).expression of p35 from the dna genome of autographa californica nuclear polyhedrosis virus (acmnpv) suppresses virus-induced apoptosis and promotes virus replication in spodoptera frugiperda (sf21) cells. to examine the molecular mechanism by which p35 prevents apoptosis in insects, sf21 cells were stably transfected with p35. neomycin-resistant cell lines that synthesized protein p35 were identified. stable transfection with p35 protected sf21 cells from apoptosis induced by actinomycin d conce ...19947966562
genetic analyses of temperature-sensitive mutations in baculovirus late expression factors.two temperature-sensitive mutants of autographa californica nuclear polyhedrosis virus were characterized with respect to late and very late gene expression. cells infected with ts317 or ts538 at the nonpermissive temperature revealed slightly reduced intracellular levels of late structural gene products including gp64 envelope, vp39 capsid, and p6.9 dna binding proteins. however, with the exception of gp64, there was a dramatic reduction in extracellular levels of the structural proteins, sugge ...19948091663
expression of the 39k promoter of autographa californica nuclear polyhedrosis virus is increased by the apoptotic suppressor p35.the 39k promoter of the baculovirus autographa californica nuclear polyhedrosis virus (acnpv) is transactivated by the viral protein ie1 and further stimulated by viral enhancer elements and the viral coactivator ie2. to identify additional viral proteins that regulate expression from the 39k promoter, we performed cotransfection experiments with clones of viral dna and a plasmid containing the chloramphenicol acetyltransferase (cat) gene under the control of the 39k promoter. our results indica ...19948091669
identification and characterization of vlf-1, a baculovirus gene involved in very late gene expression.we have identified a gene required for strong expression of the polyhedrin gene by characterizing a mutant, tsb837, of the baculovirus autographa californica nuclear polyhedrosis virus (acmnpv) which is temperature sensitive (ts) for occluded virus production at the nonpermissive temperature. marker rescue experiments utilizing an overlapping set of acmnpv genomic clones revealed that the gene responsible for the ts mutant phenotype mapped to a region between 46 and 48 map units. fragments (2.2 ...19947966564
biosynthesis and processing of the autographa californica nuclear polyhedrosis virus gp64 protein.gp64 is a major virion envelope glycoprotein of the baculovirus autographa californica multicapsid nuclear polyhedrosis virus (acmnpv). gp64 plays an important role in acmnpv infection, probably mediating penetration of one form of the virus into host cells through the endocytic pathway. gp64 also represents an excellent probe for studying the membrane glycoprotein processing capabilities of baculovirus-infected insect cells, which are used widely as a eucaryotic expression system. the goals of ...19947975226
expression of recombinant rabbit udp-glcnac: alpha 3-d-mannoside beta-1,2-n-acetylglucosaminyltransferase i catalytic domain in sf9 insect cells.udp-glcnac: alpha 3-d-mannoside beta-1,2-n-acetylglucosaminyltransferase i (gnt i; ec 2.4.1.101) catalyses a key reaction in the conversion of oligomannose to complex and hybrid n-glycans. the cytoplasmic tail and transmembrane segment of rabbit gnt i cdna were replaced with an in-frame cleavable signal sequence and the hybrid construct was inserted into the genome of autographa californica nuclear polyhedrosis virus (acmnpv) under the control of the polyhedrin promoter. sf9 insect cells were in ...19947841795
the structure and function of the first component of complement: genetic engineering approach (a review).the availability of cdna and genomic clones for the subcomponents of c1, as well as the recognition of the modular organization of serine-proteases have opened up exciting new possibilities for approaching structural problems. in this review the latest achievements of combined protein engineering, functional and structural studies are summarized. the concept of this research is to construct deletion, point and hybrid mutants of the highly homologous c1r and c1s subcomponents, to reveal the funct ...19947866721
the autographa californica nuclear polyhedrosis virus ie2 gene encodes a transcriptional regulator.the baculovirus autographa californica nuclear polyhedrosis virus (acnpv) expresses several immediate early genes in infected cells. one of these, ie2 (formerly called ien), was mapped and identified by its ability to augment ie1-mediated transactivation of the delayed early 39k gene. ie2 also stimulated the expression of reporter genes linked to the ie1 promoter. to test whether the increase in expression was due to increased mrna, primer extension analyses were performed. spodoptera frugiperda ...19948030237
primary infection of insect tracheae by autographa californica m nuclear polyhedrosis virus.previously we found that autographa californica m nuclear polyhedrosis virus infections initiated in the midguts of insect hosts are disseminated within the hosts via tracheae, elements composing the insect respiratory system. herein we report that infection of tracheae also can be initiated directly via the spiracles, exterior openings of the tracheal system to the atmosphere. infections were initiated both by direct application of viral inoculum to the spiracles and by aerosol. infections esta ...19948030276
expression and post-translational processing of a broad-spectrum organophosphorus-neurotoxin-degrading enzyme in insect tissue culture.a recombinant baculovirus, autographa californica nuclear polyhedrosis virus (acnpv), has been utilized to express the opd (organophosphate-degrading) gene from pseudomonas diminuta in insect tissue-culture cells (sf9) of the fall armyworm (spodoptera frugiperda). the broad-spectrum organophosphate hydrolase (ec 3.1.8.1) encoded by this gene is a member of a general class of enzymes [organophosphate (op) anhydrolases] that include parathion hydrolases, di-isopropyl-fluorophosphatases (dfpases), ...19948031504
recombination between genetically modified and unmodified autographa californica nuclear polyhedrosis virus in trichoplusia ni larvae.trichoplusia ni larvae have been injected with a mixture of wild-type autographa californica multiple nuclear polyhedrosis virus (acmnpv) and a mutant derivative, acrp8.uw1.lacz, which lacks the polyhedrin gene, and has the p10 gene replaced by the escherichia coli beta-galactosidase gene. following plaque assay of the haemolymph and subsequent staining for beta-galactosidase activity and scoring for polyhedra, recombinant plaques were identified and the recombination frequency estimated as 6.6% ...19947793354
evidence for the ligand-induced conversion from a dimer to a tetramer of the granulocyte colony-stimulating factor receptor.an extracellular portion of granulocyte colony-stimulating factor (g-csf) receptor, which contains an immunoglobulin-like (ig) domain and cytokine receptor homologous (crh) region, was secreted into the medium using trichoplusia ni-autographa californica nuclear polyhedrosis virus system. the gene product was purified to homogeneity mainly as a dimer (85 kda) using g-csf affinity column chromatography and gel filtration hplc, although the product existed as a monomer (45 kda) in the medium. scat ...19947805849
nuclear export of recombinant baculovirus nucleocapsids through small pore or nuclear-pore-like structure in sf9 cells.translocation of baculovirus nucleocapsids (45 nm in diameter, approximate length of 280-300 nm) from nucleoplasm to cytoplasm was studied morphologically using cryofixation and gold labeled wheat germ agglutinin (wga-gold) during recombinant autographa californica nuclear polyhedrosis virus infection in sf9 cells. nucleocapsids formed in the nucleoplasm migrated into protrusions of the nuclear envelope, but not into nuclear pore complexes. we found cross-like membranous structures. small pores ...19947808726
cloning and production of functional active recombinant hepatitis b virus surface antigen binding protein.endonexin ii present on the surface of human hepatocytes has recently been identified as a hepatitis b virus surface antigen (hbsag) binding protein. a full-length cdna clone encoding human endonexin ii was isolated from a human liver cdna library and was placed under the control of the polyhedrin promoter of autographa californica nuclear polyhedrosis virus (acnpv). infection of spodoptera frugiperda cells with recombinant virus resulted in the production of high amounts of recombinant protein. ...19947999073
reiterated dna fragments in defective genomes of autographa californica nuclear polyhedrosis virus are competent for acmnpv-dependent dna replication.we previously reported on the generation of approximately 50-kb size defective genomes (dgs) which appeared to retain less than 2.2% of the standard autographa californica nuclear polyhedrosis virus (acmnpv) dna between 85.0 and 87.2 mu while the rest of the virus dna had been largely deleted (lee and krell, j. virol., 66:4339-4347, 1992). to investigate these presumably repeated sequences further, we cloned and analyzed the most abundant hypermolar 1.80-kb xhol dna fragment as well as a minor b ...19948009853
quantification of latent mamestra brassicae nuclear polyhedrosis virus in m. brassicae insects using a pcr-scintillation proximity assay.a laboratory culture of mamestra brassicae insects (mblc) was found to harbour a latent baculovirus infection. the copy number of the occult mbnpv genome in both the mblc larvae, and in a cell line derived from the fat body of mblc was determined by the use of a rapid and convenient pcr-scintillation proximity assay (spa). the spa system relies on the use of fluomicrospheres (spa beads) coated with acceptor molecules which are capable of binding radiolabelled ligands in solution. in the assay de ...19947714043
preparation and characterization of human rheumatoid arthritic synovial fluid phospholipase a2 produced by recombinant baculovirus-infected insect cells.we prepared human rheumatoid arthritic synovial fluid phospholipase a2 (pla2) [ec 3.1.1.4] from insect cells infected with a recombinant baculovirus. the pla2 dna was designed, changing the original codons to those used frequently in the polyhedrin gene. sixteen oligo-deoxynucleotides ranging from 40 to 70 nucleotides were chemically synthesized and then assembled to form the whole pla2 gene. the gene thus synthesized was then placed under the control of the polyhedrin promoter of autographa cal ...19947798190
cloning and expression of a soluble sialidase from chinese hamster ovary cells: sequence alignment similarities to bacterial sialidases.a cdna encoding a soluble sialidase from chinese hamster ovary (cho) cells has been cloned and expressed. completely degenerate oligonucleotide primers, which were based on the amino acid sequence of peptides obtained from the purified sialidase (warner et al., glycobiology, 3, 455-463, 1993), and the polymerase chain reaction, with single-stranded cdna template, were employed to generate a unique oligonucleotide probe. the unique probe of 93 bp was used for screening a lambda gt 10 cho cell cdn ...19947949662
overexpression of human dna topoisomerase i in insect cells using a baculovirus vector.the 3645-bp human dna topoisomerase i cdna isolated by d'arpa et al. (proc. natl. acad. sci. usa 85, 1988, 2543-2547) was integrated into the autographa californica multiple nuclear polyhedrosis virus genome. the recombinant protein was expressed by infecting the sf9 insect cell line with this baculovirus and resulted in a 100-fold overexpression of human dna topoisomerase i compared to the level found in human cell lines. this 100-kda recombinant protein has the same electrophoretic mobility as ...19947950383
expression of the newcastle disease virus (ndv) fusion glycoprotein and vaccination against ndv challenge with a recombinant baculovirus.the hybrid baculovirus constructed from autographa california nuclear polyhedrosis virus (npv) and bombyx mori (silkworm) npv was used for expression of fusion glycoprotein (f) of newcastle disease virus (ndv) strain d26. the gene encoding f protein was introduced into the improved baculovirus expression vector derived from the host-range-expanded baculovirus. in spodoptera frugiperda (fall armyworm) cells infected with a recombinant baculovirus, hyf121, the expressed f protein was properly loca ...19947702510
uses of flow cytometry in virology.this article reviews some of the published applications of flow cytometry for in vitro and in vivo detection and enumeration of virus-infected cells. sample preparation, fixation, and permeabilization techniques for a number of virus-cell systems are evaluated. the use of flow cytometry for multiparameter analysis of virus-cell interactions for simian virus 40, herpes simplex viruses, human cytomegalovirus, and human immunodeficiency virus and its use for determining the effect of antiviral comp ...19947530594
identification of a membrane fusion domain and an oligomerization domain in the baculovirus gp64 envelope fusion protein.the baculovirus gp64 envelope fusion protein (gp64 efp) is the major envelope glycoprotein of the budded virion and has been shown to mediate acid-triggered membrane fusion both in virions and when expressed alone in transfected cells. using site-directed mutagenesis and functional assays for oligomerization, transport, and membrane fusion, we localized two functional domains of gp64 efp. to identify a fusion domain in the gp64 efp of the orgyia pseudotsugata multiple nuclear polyhedrosis virus ...19957533858
influence of codon usage and translational initiation codon context in the acnpv-based expression system: computer analysis using homologous and heterologous genes.codon usage by all the known gene sequences from autographa californica nuclear polyhedrosis virus (acnpv) was compared with that of firefly luciferase (luc) and the beta subunit of human chorionic gonadotropin (beta hcg) expressed to contrasting levels in the baculovirus system. the highly expressed luc gene showed a codon usage similar to acnpv genes, as reflected by a very low d-squared statistic value (0.78) and a similar g/c usage (45%) at wobble positions. however, the underexpressed beta ...19957537424
a temperature-sensitive ie1 protein of autographa californica nuclear polyhedrosis virus has altered transactivation and dna binding activities.the temperature-sensitive mutant tsb821 of autographa californica nuclear polyhedrosis virus has two nucleotide transitions in the transregulatory ie1 gene (ribiero et al. (1994) j. virol. 68, 1075-1084). these mutations result in two conservative amino acid substitutions in the encoded protein. to determine whether the mutations affect the ability of ie1 to interact with viral enhancer elements, electrophoretic mobility shift assays were performed using extracts prepared from infected cells and ...19957747488
isolation of p10 gene from bombyx mori nuclear polyhedrosis virus and study of its promoter activity in recombinant baculovirus vector system.a homologue of autographa californica npv (acnpv) p10 gene was identified and cloned from bombyx mori npv (bmnpv). bmnpv p10 gene encodes truncated protein of 70 amino acid residues that lacks carboxyl terminus comparing with the p10 protein encoded by acnpv. the putative tata box sequence and the ataag motif which is the consensus sequence of baculovirus very late promoter were conserved. a transfer vector, pbnt1, which includes the p10 promoter region of bmnpv for foreign gene expression was c ...19957547036
expression of human plasminogen activator inhibitor-2 in the baculovirus expression system.a cdna coding for human plasminogen activator inhibitor-2 (pai-2) was transferred into the genome of autographa californica nuclear polyhedrosis virus adjacent to the polyhedrin promoter. cells infected with recombinant virus synthesized a 43-kda pai-2 protein, the majority of which was secreted. the recombinant pai-2 was identical to native pai-2 purified from human placenta with respect to interaction with polyclonal antibody and inhibition of urokinase-type plasminogen activator.19957549934
production of functional human bone morphogenetic protein-2 using a baculovirus/sf-9 insect cell system.a clone of a human bone morphogenetic protein-2 (hbmp-2) cdna was obtained from a cdna library established from human dental pulp cells. after subcloning hbmp-2 cdna into autographa californica nuclear polyhedrosis virus, the recombinant baculovirus was transfected to sf-9 cells. immuno-reactive recombinant hbmp-2 (rhbmp-2) was detected by a polyclonal antibody against xenopus bmp-2 in the transfected insect cells but not in the culture media. three days after treatment with the lysate of the tr ...19957549938
replication of orgyia pseudotsugata baculovirus dna: lef-2 and ie-1 are essential and ie-2, p34, and op-iap are stimulatory genes.a transient dna replication assay was used to identify genes located within m.u. 90.5-7.0 of the orgyia pseudotsugata multinucleocapsid nuclear polyhedrosis virus (opmnpv) genome that influenced replication of a reporter plasmid containing an opmnpv origin of replication, when cotransfected into uninfected lymantria dispar cells. the viral transactivator ie-1 and a 2.4-kb subclone were found to be essential for replication. the 2.4-kb region was sequenced and open reading frames were identified. ...19957571435
efficient gene transfer into human hepatocytes by baculovirus vectors.viral vectors are the most efficient tools for gene delivery, and the search for tissue-specific infecting viruses is important for the development of in vivo gene therapy strategies. the baculovirus autographa californica nuclear polyhedrosis virus is widely used as a vector for expression of foreign genes in insect cells, and its host specificity is supposed to be restricted to arthropods. here we demonstrate that recombinant a. californica nuclear polyhedrosis virus is efficiently taken up by ...19957479733
yeast-prepro-alpha-factor-leader-region-directed synthesis and secretion of truncated human macrophage colony-stimulating factor in the silkworm bombyx mori.human macrophage colony-stimulating factor (hm-csf) cdna joined to the leader region of the precursor of the yeast mating pheromone alpha-factor (mf alpha l) was expressed at high levels in bmn cells and in silkworm (bombyx mori) larvae, using recombinant bombyx mori nuclear polyhedrosis virus, as a vector. the biological activity of rhm-csf detected in the haemolymph was 1 x 10(6) colony-formation units/ml, approximately half of the expression level directed by the native signal peptide of hm-c ...19957710703
beet western yellows luteovirus capsid proteins produced by recombinant baculoviruses assemble into virion-like particles in cells and larvae of bombyx mori.we subcloned various constructs of the beet western yellows luteovirus (bwyv) 3' proximal genes into bombyx mori nuclear polyhedrosis virus (bmnpv) transfer vectors and constructed recombinant bmnpvs. the recombinant bmnpvs were used to infect bmn cells and b. mori larvae. protein expression was analyzed by sds-page and immunoblot analysis, and the bwyv-encoded capsid protein (cp), p19, readthrough protein (rt), and a modified capsid-readthrough protein (cp-rt*) were detected in bmn cells infect ...19957483264
use of juvenile hormone esterase as a novel reporter enzyme in the baculovirus expression system.juvenile hormone esterase (jhe) has a number of characteristics favorable for use as a reporter enzyme. it is extremely stable under a variety of adverse conditions including in organic solvent. jhe is easily detected by a rapid and sensitive colorimetric assay, and detection is facilitated by export of the enzyme from the cell. its use is illustrated in the baculovirus expression system by promoter studies and evaluation of culture conditions necessary for optimal production of recombinant prot ...19957730431
functional expression of an alpha anti-insect scorpion neurotoxin in insect cells and lepidopterous larvae.the leiurus quinquestriatus hebraeus alpha anti-insect toxin (lqh alpha it) cdna was engineered into the autographa californica nuclear polyhedrosis virus (acnpv) genome. insect cells infected with the recombinant virus secreted a functional lqh alpha it polypeptide. spodoptera littoralis and heliothis armigera larvae injected with recombinant budded virus, showed typical intoxication symptoms. this recombinant virus showed enhanced insecticidal potency against h. armigera larvae compared with w ...19957498537
transcriptional regulation of cell line-dependent, baculovirus-mediated expression of foreign genes.cell line-dependent expression of foreign genes in the baculovirus system was investigated using a recombinant vac beta hcg-luc virus carrying two reporter genes--beta subunit of human chorionic gonadotropin (beta hcg) and luciferase (luc)--placed under the transcriptional control of the autographa californica nuclear polyhedrosis virus (acnpv) polyhedrin gene promoters. five different lepidopteran cell lines derived from spodoptera frugiperda (sf21 and sf9), bombyx mori (bmn and bm5), and trich ...19957530452
p10 genes of bombyx mori nuclear polyhedrosis virus and autographa californica multiple nuclear polyhedrosis virus.ecor i-p fragment has been cloned from autographa californica multiple nuclear polyhedrosis virus (acmnpv) genomic dna and used as a probe. 0.5-kb and 1.1-kb fragments including p10 gene from bombyx mori nuclear polyhedrosis virus (bmnpv) have been hybridized. the p10 orf was located in the ecor i-r fragment. initiation codon atg of p10 from bmnpv has been mutated by pcr, and the atg region became a bgl ii site. a novel transfer vector pbmacpv-1 has been constructed using both the p10 5'-flankin ...19957695816
transcriptional enhancer activity of hr5 requires dual-palindrome half sites that mediate binding of a dimeric form of the baculovirus transregulator ie1.the hr5 enhancer element stimulates early viral transcription and may function as an origin of dna replication for autographa californica nuclear polyhedrosis virus (acmnpv). the smallest functional unit of hr5 is a 28-bp repeat consisting of an imperfect palindrome (28-mer). to identify essential sequences and examine the molecular basis of hr5 activity, the effects of site-directed mutations on transcriptional enhancement by the 28-mer and binding of the acmnpv transregulator ie1 were investig ...19957636981
biochemical analysis of the n-glycosylation pathway in baculovirus-infected lepidopteran insect cells.the baculovirus-insect cell system is used routinely for foreign glycoprotein production, but the precise nature of the n-glycosylation pathway in this system remains unclear. some studies indicate that these cells cannot process n-linked oligosaccharides to complex forms containing outer-chain galactose and sialic acid, while others indicate that they can. in this study, we used the major virion envelope glycoprotein of the baculovirus autographa california multicapsid nuclear polyhedrosis viru ...19957571420
the baculovirus transactivator ie1 binds to viral enhancer elements in the absence of insect cell factors.the transregulatory ie1 protein of autographa californica nuclear polyhedrosis virus binds to the viral enhancer element hr5. to test whether ie1 binds independently of host cell factors, ie1 was translated in rabbit reticulocyte extracts and tested for dna binding activity by an electrophoretic mobility shift assay. complexes with the hr5 probe were detected with translation reaction mixtures primed with ie1 rna but not with control translation reaction mixtures. however, the dna-protein comple ...19957769721
n-glycosylated polypeptides synthesized in the early phase of acnpv infected insect cells.infected cell specific polypeptides (icsp) in autographa californica nuclear polyhedrosis virus (acnpv) infected spodoptera frugiperda cell line, sf9, were radiolabelled with [14c] mannose and the labelled proteins were monitored at various time intervals. a major glycoprotein of molecular size of 64 kda appears as early as 3h post infection (p.i.) which peaks at 12h p.i., but in presence of tunicamycin this protein is not labelled. two other glycoproteins of molecular size 67 kda and 63 kda app ...19957773189
developmental resistance in fourth instar trichoplusia ni orally inoculated with autographa californica m nuclear polyhedrosis virus.larvae of lepidopteran insects commonly become increasingly resistant to baculovirus infections as they age. the mechanism responsible for this development resistance is not known, but the phenomenon does not occur if the viral inoculum is administered intrahemocoelically instead of orally, which is the natural route of infection. this observation indicates that the factors mediating developmental resistance are operative during infection of the primary target tissue, the larval midgut, and not ...19957778273
identification and analysis of a putative origin of dna replication in the choristoneura fumiferana multinucleocapsid nuclear polyhedrosis virus genome.a recombinant plasmid containing the choristoneura fumiferana multinucleocapsid nuclear polyhedrosis virus (cfmnpv) hindiii r fragment (m.u. 2.2-3.9) was shown to undergo cfmnpv infection-dependent dna replication in cf-124t cells. replication of this dna sequence was detectable by 24 hr p.i. and did not appear to have resulted as a consequence of recombination with the virus genome. replication was inhibited by mimosine, an inhibitor of eukaryotic dna replication. these data suggest that hindii ...19957778276
comparative pathogenesis of autographa californica m nuclear polyhedrosis virus in larvae of trichoplusia ni and heliothis virescens.we compared early viral pathogenesis and dose-mortality relationships for larvae of two highly susceptible hosts, trichoplusia ni and heliothis virescens, using a construct of acmnpv containing the lacz reporter gene. larvae were inoculated either as newly molted fourth instars (4(0)) or 15 hr after the molt (4(15)). in 4(0)-inoculated larvae, first lacz expression was detected in the midgut epithelium of t. ni at 4 hr postinoculation (hpi) compared to 18 hpi in h. virescens, and systemic infect ...19957778288
the baculovirus gp64 envelope fusion protein: synthesis, oligomerization, and processing.the baculovirus gp64 envelope fusion protein (gp64 efp) is a class i integral membrane protein that enters the secretory pathway and is oligomerized and extensively processed during transport to the plasma membrane. the kinetics of gp64 efp biosynthesis, oligomerization, and processing in orgyia pseudotsugata multicapsid nuclear polyhedrosis virus (opmnpv)-infected lymantria dispar cells were examined by pulse label, pulse-chase, and immunoprecipitation experiments. relative rates of gp64 efp sy ...19957778291
nucleotide sequence and transcriptional analysis of the gp41 gene of spodoptera frugiperda nuclear polyhedrosis virus.the spodoptera frugiperda multiple nucleocapsid nuclear polyhedrosis virus (sfmnpv) gp41 structural protein gene was located in the 1.9 kbp ecori-s fragment and sequenced. an open reading frame (orf) of 999 nucleotides was detected that encoded a protein of 332 amino acids. the gp41 gene transcript was detected after 12 h post-infection (p.i.) and remained detectable at 48 h p.i. two major mrnas, about 1.6 and 2.8 kb in length, were determined by northern blot analysis. primer extension analysis ...19957782772
mutations in the autographa californica multinucleocapsid nuclear polyhedrosis virus 25 kda protein gene result in reduced virion occlusion, altered intranuclear envelopment and enhanced virus production.serial passage of nuclear polyhedrosis viruses (npvs) through cultured cell lines results in the appearance of mutants with a complex phenotype referred to as the 'few polyhedra' (fp) phenotype. the altered plaque morphology and reduced occlusion production associated with the fp phenotype have been observed in autographa californica multinucleocapsid nuclear polyhedrosis virus (acmnpv) bearing mutations in the gene encoding the 25 kda protein (25k gene). in this study, we sequenced the 25k gene ...19957782773
differential transcription of baculovirus late and very late promoters: fractionation of nuclear extracts by phosphocellulose chromatography.an in vitro transcription system based on cytidine-free cassette was developed for the late 39k gene and the very late polyhedrin gene of autographa californica nuclear polyhedrosis virus (acnpv). optimization of transcription conditions revealed that a preincubation step was not required for transcription of late and very late promoters, although preincubation was essential for efficient transcription from an early promoter. the 39k and polyhedrin constructs were actively transcribed by nuclear ...19957707516
evaluation of protein-a linked monoclonal antibody latex agglutination test for diagnosis of nuclear polyhedrosis virus (bmnpv) of silkworm bombyx mori l.the symptomology of bmnpv infection in bombyx mori l depends on the stages of infection. discernible symptoms develop at later stages of infection, which leads to improper diagnosis and poor crop yield with sericulturists. in the present study development of direct and protein-a linked monoclonal antibody latex (palmal) agglutination test for the detection of bmnpv infection in silkworm is described. latex beads were precoated with protein-a and then sensitised with monoclonal antibody ma-231 (1 ...19957629276
high level synthesis and secretion of human urokinase using a late gene promoter of the autographa californica nuclear polyhedrosis virus.a cdna encoding human urokinase was inserted into the autographa californica nuclear polyhedrosis virus (acnpv) genome at the polyhedrin gene locus under control of a duplicated copy of the late, basic protein gene promoter. the insect-derived urokinase was produced predominantly in the form of single-chain, pro-urokinase, with a molecular mass of 50 kda, and demonstrated fibrinolytic activity. synthesis and secretion of urokinase was first detected at 6 hours post-infection and continued steadi ...19957766008
expression of the human interleukin-2 receptor gamma chain in insect cells using a baculovirus expression vector.the gene encoding the gamma-chain of the human interleukin-2 receptor was expressed in lepidopteran insect cells using the baculovirus expression vector system. the corresponding gene was inserted under the polyhedrin promoter of the autographa californica nuclear polyhedrosis virus and expressed in the spodoptera frugiperda insect cell line sf9 during viral infection. the recombinant receptor protein was identified by immunoblotting in cell lysates, prepared from insect cells infected with the ...19957899821
deletion of the baculovirus ecdysteroid udp-glucosyltransferase gene induces early degeneration of malpighian tubules in infected insects.deletion of the ecdysteroid udp-glucosyltransferase gene (egt) from the autographa californica nuclear polyhedrosis virus (acnpv) genome increases the speed of killing of this virus (d. r. o'reilly and l. k. miller, bio/technology 9:1086-1089, 1991). second-instar spodoptera exigua larvae are killed more rapidly by the egt deletion mutant of acnpv than by wild-type acnpv. unlike wild-type acnpv-infected larvae, larvae infected with an egt deletion mutant molt and resume feeding as mock-infected ...19957769717
properties of a baculovirus mutant defective in the protein phosphatase gene.autographa california nuclear polyhedrosis virus (acmnpv) contains a gene, ptp, encoding a protein tyrosine/serine phosphatase, bv-ptp. to investigate the biological function of ptp in the baculoviral replication cycle, we constructed a recombinant baculovirus, vptpdel, in which the catalytically active site of bv-ptp was deleted. although the vptpdel mutant was viable in cell culture, it was partially defective in occluded virus production in sf-21 but not tn-368 cell lines. sf-21 cells infecte ...19957769718
characterization of v-cath, a cathepsin l-like proteinase expressed by the baculovirus autographa californica multiple nuclear polyhedrosis virus.autographa californica multiple nuclear polyhedrosis virus (acmnpv) contains a 966 bp orf that encodes a papain type cysteine proteinase with cathepsin l-like characteristics. using western blot analysis of infected cell extracts we showed that v-cath proteinase has 35.5 kda and 32 kda precursor forms which are processed to a 27.5 kda mature form in a manner characteristic of papain and cathepsin l. v-cath proteinase activity was greatest under acidic conditions (ph 5.0) and was reduced in the p ...19957730794
overexpression of bombyx mori prothoracicotropic hormone using baculovirus vectors.recombinant baculoviruses were constructed that express the cdna encoding the prothoracicotropic hormone (ptth) of bombyx mori. this hormone stimulates the production of ecdysteroids by the insect's prothoracic glands. two groups of viruses were constructed, expressing either the entire cdna encoding prepro-ptth, or a synthetic chimeric gene encoding a signal peptide fused to the mature ptth subunit. in both cases, the genes were expressed in wild-type autographa californica nuclear polyhedrosis ...19957742834
the cagt motif functions as an initiator element during early transcription of the baculovirus transregulator ie-1.the highly conserved tetranucleotide cagt is located at the rna start site of the transregulator gene ie-1 of autographa californica nuclear polyhedrosis virus (acmnpv). the presence of this motif within numerous baculovirus early promoters and its similarity to transcriptional initiators suggested a fundamental role in viral transcription regulation. to determine the function of the cagt motif, site-specific mutations were introduced within the ie-1 promoter fused to a reporter gene within acmn ...19957745705
the lef-3 gene of autographa californica nuclear polyhedrosis virus encodes a single-stranded dna-binding protein.the autographa californica nuclear polyhedrosis virus (acnpv) replicates in the nuclei of infected cells and encodes several proteins required for viral dna replication. as a first step in the functional characterization of viral replication proteins, we purified a single-stranded dna-binding protein (ssb) from acnpv-infected insect cells. nuclear extracts were chromatographed on single-stranded dna agarose columns. an abundant protein with an apparent molecular weight of 43,000 was eluted from ...19957745748
the autographa californica nuclear polyhedrosis virus homologous region 1a: identical sequences are essential for dna replication activity and transcriptional enhancer function.hr1a consists of two 30-bp imperfect palindrome sequences separated by 58 bp and each palindrome contains a naturally occurring ecori site at its core. plasmid subclones of the hr1a-containing acmnpv hindiii-n fragment were examined for their ability to replicate in virus-infected (spodoptera frugiperda) sf9 cells, and to stimulate transcription when linked in cis with a 39k gene promoter-beta-glucuronidase fusion and cotransfected into cells along with a plasmid (ple-1) containing the gene enco ...19957747446
expression of the ie1 transactivator of autographa californica nuclear polyhedrosis virus during viral infection.the immediate-early ie1 protein of autographa californica nuclear polyhedrosis virus (acmnpv) is an important regulator of viral gene transcription. to provide a tool for further analysis of the expression and function of ie1, a polyclonal antiserum was raised against ie1 expressed in bacteria. immunoblot analysis of infected cell lysates was used to monitor the accumulation of ie1 throughout the viral life cycle. when extracts were prepared in the presence of phosphatase inhibitors, only one pr ...19957747489
synthesis and processing of the rubella virus p110 polyprotein precursor in baculovirus-infected spodoptera frugiperda cells.in order to study the processing of rubella virus (rv) structural proteins (capsid protein, of 33 kda; e2 of 42-47 kda; and e1 of 58 kda) in spodoptera frugiperda (fall armyworm) cells, a 24s cdna encoding the polyprotein precursor, p110, was inserted under the transcriptional regulation of the polyhedrin gene promoter of the autographa californica nuclear polyhedrosis virus (acnpv) and expressed during viral infection. by immunoblot analysis using antibodies directed against whole rv and the in ...19957754676
identification and preliminary characterization of a chitinase gene in the autographa californica nuclear polyhedrosis virus genome.a functional chitinase gene (chia) has been identified in the genome of the autographa californica nuclear polyhedrosis virus (acmnpv). it is expressed in the late phase of virus replication in insect cells. high levels of both endo- and exochitinase activity were detected by 12 hr p.i. and remained stable throughout infection. an acmnpv chia protein-specific antibody was prepared using recombinant material prepared in bacteria. this was used to demonstrate that a product of approximately 58 kda ...19957571437
characterization, sequencing and phylogeny of the ecdysteroid udp-glucosyltransferase gene from two distinct nuclear polyhedrosis viruses isolated from choristoneura fumiferana.the ecdysteroid udp-glucosyltransferase (egt) gene isolated from a plaque-purified isolate of choristoneura fumiferana multinucleocapsid nuclear polyhedrosis virus (cfmnpv) was compared to its homologue from a defective mnpv virus (cfdef) present in wild type virus populations infecting the eastern spruce budworm, c. fumiferana. the egt genes were located in the same relative position within the virus genomes and their genomic location and arrangement were similar to that found in autographa cal ...19957595348
molecular structure and function of cd4 on murine egg plasma membrane.in the present study, the expression of the cd4 molecule on murine egg plasma membrane was confirmed by the indirect immunofluorescence (iif) method. the full-length cd4 cdna from murine eggs was synthesised by the reverse transcriptase-polymerase chain reaction (rt-pcr) method and its authenticity verified by southern blot hybridisation using an end-labelled internal oligonucleotide. the results of dna sequencing showed that the nucleotide sequence of the cdna of cd4 from murine egg mrna was id ...19957613876
identification, sequence, and transcriptional analysis of lef-3, a gene essential for orgyia pseudotsugata baculovirus dna replication.using a transient complementation assay for dna replication of an origin-containing reporter plasmid, a 2.4-kb region (m.u. 48.3-50.1) of the orgyia pseudotsugata multinucleocapsid nuclear polyhedrosis virus (opmnpv) genome was identified that contains a gene essential for opmnpv dna replication. this region was sequenced and open reading frames were identified. replication assays using subclones from this region identified a gene called late expression factor 3 (lef-3), as the essential replica ...19957618274
secretion of active human lecithin-cholesterol acyltransferase by insect cells infected with a recombinant baculovirus.difficulties in purifying the plasma enzyme lecithin-cholesterol acyltransferase (lcat) have hampered detailed studies of its (patho)physiological role in lipoprotein metabolism and of structure-function relationships. potentially, baculovirus-driven expression systems offer a powerful means to produce significant amounts of lcat. accordingly, full-length lcat cdna was cloned into pvl 1392, a high-level expression derivative of autographa californica nuclear polyhedrosis virus (acnpv), and the r ...19957619064
heterologous expression and enzymatic properties of a selenium-independent glutathione peroxidase from the parasitic nematode brugia pahangi.a full-length cdna from the parasitic nematode brugia pahangi encoding a secreted homolog of glutathione peroxidase in which the codon for the active site selenocysteine is substituted naturally by a cysteine codon has been expressed in spodoptera frugiperda (insect) cells via autographa californica nuclear polyhedrosis virus (baculovirus). the recombinant protein was glycosylated and secreted from the cells in tetrameric form. the purified protein showed glutathione peroxidase activity with a r ...19957629152
Refresh
firstprev
12345678910...
nextlast
Displaying items 801 - 900 of 1347