| plaque assay of heliothis zea baculovirus employing a mixed agarose overlay. | the nuclear polyhedrosis virus of heliothis zea has been titrated in heliothis zea cells by the plaque method, using 1 percent mixed agarose containing a mixture of seakem and ultra pure agarose. visible plaques, formed 8 days postinfection, ranged in diameter from 0.5 to 2 mm. dose-response experiments indicated that a single particle initiated the formation of a plaque. the titration of heliothis zea baculovirus by the newly described plaque method provides an accurate technique for the determ ... | 1981 | 7213016 |
| 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 ... | 1995 | 7479733 |
| 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 ... | 1995 | 7483264 |
| 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 ... | 1995 | 7498537 |
| 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 ... | 1995 | 7530452 |
| 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 ... | 1994 | 7530594 |
| 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 ... | 1995 | 7533858 |
| 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 ... | 1995 | 7537424 |
| 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 ... | 1995 | 7547036 |
| 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. | 1995 | 7549934 |
| 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 ... | 1995 | 7549938 |
| 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 ... | 1995 | 7629276 |
| 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 ... | 1995 | 7636981 |
| 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 ... | 1995 | 7695816 |
| 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 ... | 1994 | 7702510 |
| 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 ... | 1995 | 7710703 |
| 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 ... | 1995 | 7730431 |
| 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 ... | 1995 | 7754676 |
| 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 ... | 1995 | 7595348 |
| expression of pe38 and ie2, viral members of the c3hc4 finger family, during baculovirus infection: pe38 and ie2 localize to distinct nuclear regions. | the pe38 gene of autographa californica nuclear polyhedrosis virus represents one of the major early transcripts after viral infection. the function of the pe38 protein, which contains a c3hc4 zinc finger motif, is still not understood. we have raised polyclonal antiserum against the pe38 protein, pe38, produced in bacteria to investigate pe38 expression in the course of infection. a approximately 38-kda polypeptide is first detectable at 2 h postinfection and decreases rapidly after 24 h. durin ... | 1995 | 7636971 |
| anticarsia gemmatalis nuclear polyhedrosis virus replication in serum-free and serum-reduced insect cell cultures. | in order to develop a financially feasible process to produce anticarsia gemmatalis nuclear polyhedrosis virus in cell culture, we developed a lipidic supplement to replace fetal calf serum in insect cell culture media. the supplement, prepared with an extract of lipids from hen egg yolk, allowed us to reduce the contents of serum in the culture medium from 10% to 1%. iplb-sf-21 cells could be kept along consecutive passages in serum-reduced medium. the replication of agnpv in heyle-supplemented ... | 1993 | 7764195 |
| production of human alkaline phosphatase, a secreted, glycosylated protein, from a baculovirus expression system and the attachment-dependent cell line trichoplusia ni bti-tn 5b1-4 using a split-flow, air-lift bioreactor. | a split-flow, air-lift bioreactor for the cultivation of insect cells to produce recombinant protein is described. it can be used advantageously with attached cell systems. this bioreactor incorporates two sections: a rise and a downcomer. trichoplusia ni bti-tn 5b1-4 cells are grown on a support material of glass beads or microcarriers placed in the downcomer. this cell line is more productive than other commonly used insect cell lines, but it has the disadvantage of being difficult to use at l ... | 1993 | 7764358 |
| 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 ... | 1995 | 7766008 |
| baculovirus-driven expression and purification of glycine receptor alpha 1 homo-oligomers. | the glycine receptor is a ligand-gated anion channel protein of postsynaptic membranes. we expressed a homo-oligomeric receptor composed of human alpha 1 subunits in spodoptera frugiperda cells by infection with a recombinant autographa californica nuclear polyhedrosis virus. a substantial fraction of the recombinant receptor was incorporated as a functional channel protein into the cell's plasma membrane at expression levels 4- to 30-fold higher than in other eukaryotic heterologous expression ... | 1995 | 7635206 |
| construction and adhesive properties of a soluble madcam-1-fc chimera expressed in a baculovirus system: phylogenetic conservation of receptor-ligand interaction. | madcam-1 is a high endothelial venule adhesion molecule composed of immunoglobulin and mucin-like domains which binds the leucocyte integrin lpam-1 (alpha 4 beta 7), and is largely responsible for the selective homing of lymphocytes to mucosal tissues. a novel soluble form of mouse madcam-1 which is normally membrane bound has been produced by joining the extracellular region of the receptor to the fc domain of human igg1. the madcam-1-fc cdna was inserted into the genome of autographa californi ... | 1995 | 7631157 |
| 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 ... | 1995 | 7629152 |
| 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 ... | 1995 | 7619064 |
| 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 ... | 1995 | 7778273 |
| 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 ... | 1995 | 7618274 |
| the wild-type autographa californica nuclear polyhedrosis virus induces apoptosis of spodoptera littoralis cells. | spodoptera littoralis cells infected with the autographa californica multiple nuclear polyhedrosis virus (acmnpv) yielded significantly lower budded virus titers than spodoptera frugiperda-infected cells and produced very low levels of polyhedrin. relative to acmnpv-infected s. frugiperda sf9 cells viral dna replication was severely reduced in spodoptera littoralis sl2 cells. microscopic examination of sl2-infected cells revealed progressive cell blebbing starting at 6-8 hr postinfection and cul ... | 1995 | 7778284 |
| identification, localization, transcription, and sequence analysis of the choristoneura fumiferana nuclear polyhedrosis virus dna polymerase gene. | the location of the choristoneura fumiferana baculovirus dna polymerase gene was determined by hybridization analysis using a probe prepared from the previously identified polymerase gene from the autographa californica multiple nuclear polyhedrosis virus. dna sequence analysis revealed that the choristoneura fumiferana baculovirus dna polymerase gene consists of 2970 base pairs encoding 990 amino acids (114.2 kda). transcriptional analysis demonstrated that overlapping transcripts of 3.2 and 4. ... | 1995 | 7778286 |
| 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 ... | 1995 | 7613876 |
| 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 ... | 1995 | 7571437 |
| 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. ... | 1995 | 7571435 |
| 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 ... | 1995 | 7571420 |
| 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% ... | 1994 | 7793354 |
| 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 ... | 1994 | 7798190 |
| effect of temperature and oxygen on cell growth and recombinant protein production in insect cell cultures. | the effect of temperature and o2 saturation on the production of recombinant proteins beta-galactosidase and human glucocerebrosidase by spodoptera frugiperda cells (sf9) infected with recombinant autographa californica nuclear polyhedrosis virus was investigated. the rates of cell growth, glucose consumption, o2 consumption and product expression were measured at temperatures between 22 degrees c and 35 degrees c. the results indicated that possible o2 limitation may be alleviated without compr ... | 1993 | 7763472 |
| 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 ... | 1995 | 7747489 |
| 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 ... | 1995 | 7747488 |
| 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 ... | 1995 | 7747446 |
| 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 ... | 1995 | 7745748 |
| 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 ... | 1995 | 7745705 |
| 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 ... | 1995 | 7742834 |
| 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 ... | 1995 | 7730794 |
| 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 ... | 1994 | 7714043 |
| 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 ... | 1995 | 7707516 |
| inhibition of bombyx mori nuclear polyhedrosis virus (npv) replication by the putative dna helicase gene of autographa californica npv. | coinfection of bombyx mori nuclear polyhedrosis virus (bmnpv) with autographa californica npv (acnpv) in the bmnpv-permissive bmn cell line resulted in the complete inhibition of bmnpv replication. coinfected bmn cells exhibited an atypical cytopathic effect (cpe) and synthesis of viral and host proteins was dramatically attenuated by 5 h postinfection (p.i.) and nearly completely blocked by 24 h p.i. viral transcription, however, appeared to occur normally during both early (5-h-p.i.) and late ... | 1993 | 7690422 |
| proteolysis of p6.9 induced by cytochalasin d in autographa californica m nuclear polyhedrosis virus-infected cells. | cytochalasin d, a fungus-derived compound that interferes with actin polymerization, inhibits autographa californica m nuclear polyhedrosis virus production in infected spodoptera frugiperda (iplb-sf-21) cells. cytochalasin d appears to inhibit nucleocapsid morphogenesis by interfering with nucleoprotein packaging. we were interested in determining, therefore, whether the drug affected the synthesis or processing of p6.9, the major core protein involved in nucleoprotein packaging. we found that ... | 1995 | 7871717 |
| baculovirus mediated high-level expression of luciferase in silkworm cells and larvae. | bombyx mori nuclear polyhedrosis virus (bmnpv)-based baculovirus expression system exploits silkworm larvae as an economical alternative to large-scale cell cultures for production of biomolecules. to generate recombinant bmnpv at high frequencies, we have achieved high efficiency transfection of b. mori cells, bmn, through lipofection. optimal conditions for lipofection were standardized by quantification of the transient expression level of firefly luciferase (luc) reporter gene under control ... | 1995 | 7669303 |
| differential requirements for baculovirus late expression factor genes in two cell lines. | a plasmid library of 18 late expression factor (lef) genes (lef library) from the baculovirus autographa californica nuclear polyhedrosis virus (acmnpv) supports transient expression from a late viral promoter in the sf-21 cell line, derived from spodoptera frugiperda. we found, however, that this lef library was unable to support expression from the same promoter in the tn-368 cell line, derived from trichoplusia ni, which is also permissive for acmnpv replication. to identify the additional fa ... | 1995 | 7666527 |
| 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 ... | 1995 | 7899821 |
| baculovirus-mediated production of the human growth hormone in larvae of the silkworm, bombyx mori. | to express the cdna encoding human growth hormone (hgh) in larvae of bombyx mori, b. mori nuclear polyhedrosis virus (bmnpv) was employed as an expression vector. for the construction of the recombinant virus, the hgh cdna was inserted into the downstream of the strong polyhedrin promoter to achieve a high level expression. immunoblot analysis revealed that the virus-mediated hgh was synthesized in the larvae and secreted into the hemolymph. the yield of the recombinant hgh synthesized in the la ... | 1995 | 7646491 |
| 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 ... | 1994 | 7933125 |
| 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 ... | 1994 | 7949662 |
| 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 ... | 1994 | 7950383 |
| 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 ... | 1995 | 7769717 |
| 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 ... | 1994 | 7964609 |
| 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 ... | 1995 | 7769718 |
| 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 ... | 1995 | 7769721 |
| 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 ... | 1995 | 7773189 |
| 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 ... | 1995 | 7778276 |
| 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 ... | 1995 | 7778288 |
| 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 ... | 1995 | 7778291 |
| host-specific transcription of baculovirus genes. | we examined the differential replication of autographa californica multicapsid nuclear polyhedrosis virus (acmnpv; family: baculoviridae) in spodoptera frugiperda (sf) and bombyx mori (bm) cell lines. our previous studies have shown that infection of bm cells is abortive; infectious progeny is not produced, and although virogenic stroma is produced, complete virions or inclusion bodies are not assembled. we designed the present study to determine the extent of infected-cell-specific polypeptides ... | 1993 | 7763702 |
| 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 ... | 1994 | 7996129 |
| 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 ... | 1995 | 7782772 |
| 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 ... | 1995 | 7782773 |
| 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 ... | 1994 | 7805849 |
| 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 ... | 1994 | 7808726 |
| eighteen baculovirus genes, including lef-11, p35, 39k, and p47, support late gene expression. | we report the identification of four additional genes of the autographa californica nuclear polyhedrosis virus involved in expression from a late baculovirus promoter in transient expression assays. three of these genes, p35, 39k, and p47, have been previously described. the role of the p35 gene product in late gene expression may be related to its ability to block apoptosis, since two other baculovirus genes also known to block apoptosis, cp-iap and op-iap, were able to functionally replace p35 ... | 1995 | 7815564 |
| the roles of eighteen baculovirus late expression factor genes in transcription and dna replication. | a set of 18 plasmid subclones of the autographa californica nuclear polyhedrosis virus genome supports expression from a late viral promoter in transient expression assays (j. w. todd, a. l. passarelli, and l. k. miller, j. virol. 69:968-974, 1995). using this set of plasmids, we have assigned a role for each of the 18 genes required for optimal late gene expression with respect to its involvement at the levels of transcription, translation, and/or dna replication. rnase protection analyses demo ... | 1995 | 7815565 |
| expression and functional analysis of a baculovirus gene encoding a truncated protein kinase homolog. | autographa californica nuclear polyhedrosis virus (acmnpv) potentially encodes a 215-amino acid polypeptide containing 6 out of 11 motifs conserved among eukaryotic protein kinases (morris et al., virology 200, 360-369, 1994). we examined the expression of this gene, named pk2, at the transcriptional and translational levels and the possible role of the gene during baculovirus replication in cell culture and insect larvae. northern (rna) blot analysis revealed that pk2 was transcribed primarily ... | 1995 | 7831787 |
| nucleotide sequence and transcriptional analysis of the dna polymerase gene of bombyx mori nuclear polyhedrosis virus. | a gene encoding a putative dna polymerase (pol) of bombyx mori nuclear polyhedrosis virus (bmsnpv) was cloned and sequenced. the gene included an open reading frame (orf) encoding a polypeptide of 988 amino acids with a predicted molecular mass of 114.65 kda. the deduced amino acid sequence of the bmsnpv pol orf showed an overall identity of 96 and 45% to those of the autographa californica npv (acmnpv) pol orf and the lymantria dispar npv pol orf, respectively, and contained sequences conserved ... | 1995 | 7831799 |
| ubiquitin is attached to membranes of baculovirus particles by a novel type of phospholipid anchor. | purified budded virions of autographa californica nuclear polyhedrosis virus (acnpv) contain abundant amounts of free ubiquitin, which has an altered electrophoretic mobility on sds gels as compared with standard ubiquitin. phase extraction of virion proteins with triton x-114 indicated that the modified form of ubiquitin behaved as an integral membrane protein. the membrane-bound form of ubiquitin was labeled with both phosphate and palmitate, and its electrophoretic mobility was altered by tre ... | 1995 | 7834750 |
| sequence analysis and transcriptional mapping of the orf-2 gene of autographa californica nuclear polyhedrosis virus. | sequencing of the dnapol promoter region of autographa californica nuclear polyhedrosis virus (acnpv) revealed an overlapping open reading frame (orf) in an antisense orientation, referred to as orf-2. analysis of the orf-2 deduced amino-acid sequence revealed two short regions of homology with a similar orf from lymantria dispar nuclear polyhedrosis virus (ldnpv). two 3' processing signals of this gene, expressed late during infection, were shown to be located on the orf-2 stop codon and 162 nu ... | 1995 | 7835700 |
| 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 ... | 1994 | 7841795 |
| overlapping tata-dependent and tata-independent early promoter activities in the baculovirus gp64 envelope fusion protein gene. | in previous studies to characterize basal and activated transcription from the early promoter of the gp64 envelope fusion protein (efp) gene of the orgyia pseudotsugata multicapsid nuclear polyhedrosis virus, the tata box was identified as a functional element, essential for basal transcription from a minimal promoter construct. in the current study, we used discrete deletions and multiple point mutations that removed the functional tata box from larger promoter constructs of the gp64 efp gene t ... | 1995 | 7853477 |
| 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 ... | 1994 | 7866721 |
| identification of essential trans-acting regions required for dna replication of the orgyia pseudotsugata multinucleocapsid nuclear polyhedrosis virus: lef-1 is an essential replication gene. | a transient replication assay for the identification of baculovirus genes that are essential for replication of an origin-containing reporter plasmid was established for the orgyia pseudotsugata multinucleocapsid nuclear polyhedrosis virus (opmnpv). using a replication origin located on the opmnpv hindiii-n fragment, we identified a subset of cosmids and plasmids from an opmnpv cosmid library that was able to supply all the essential trans-acting factors and support replication of the origin-con ... | 1995 | 7886946 |
| identification and characterization of a second putative origin of dna replication in a baculovirus of orgyia pseudotsugata. | a 7.5-kb region (96.8-2.5 m.u.), called op5, of the orgyia pseudotsugata multinucleocapsid nuclear polyhedrosis virus (opmnpv) genome that contains an origin of dna replication was characterized. this region replicates several times more efficiently and is unrelated to the previously identified putative origin of replication located on the viral hindiii-n fragment. in contrast to hindiii-n, the origin on op5 contains repeated sequences with limited sequence identity to the homologous regions fro ... | 1995 | 7886962 |
| 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 ... | 1994 | 7918113 |
| 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 ... | 1994 | 7963591 |
| 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 ... | 1994 | 7964631 |
| 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 ... | 1994 | 7966562 |
| 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 ... | 1994 | 7966564 |
| 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 ... | 1994 | 7975226 |
| early transcription of the ie-1 transregulator gene of autographa californica nuclear polyhedrosis virus is regulated by dna sequences within its 5' noncoding leader region. | the ie-1 gene of autographa californica nuclear polyhedrosis virus (acmnpv) encodes a transregulatory protein (ie1) which accelerates the expression of early and late virus genes. transcription of ie-1 occurs immediately upon infection from a conserved cagt motif and continues into the late phases. to examine the mechanisms by which ie-1 expression is regulated, cis-acting control elements within the ie-1 promoter were identified by constructing hybrid early promoters and by using site-directed ... | 1995 | 7983706 |
| lymantria dispar nuclear polyhedrosis virus homologous regions: characterization of their ability to function as replication origins. | homologous regions (hrs) were identified in the lymantria dispar nuclear polyhedrosis virus (ldmnpv) genome. a 1.58-kb region surrounding hr4 was sequenced and found to have two distinct domains. domain i (about 600 bp) is composed of seven repeats of about 80 bp including a series of palindromes containing mlui sites and overlapping xhoi and saci sites. domain ii (about 700 bp) is composed of eight partially repeated sequences of 60 to 100 bp containing a 15- to 25-bp sequence that is 80 to 100 ... | 1995 | 7983712 |
| 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 ... | 1994 | 7986747 |
| 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 ... | 1994 | 7996162 |
| 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. ... | 1994 | 7999073 |
| baculovirus expression of human basic fibroblast growth factor from a synthetic gene: role of the kozak consensus and comparison with bacterial expression. | synthetic genes encoding the 146 and 155 amino acid forms of human basic fibroblast growth factor (bfgf) were constructed with codon usage biased towards the polyhedrin-encoding gene of autographa californica nuclear polyhedrosis virus (acnpv). expression of both bfgf genes in spodoptera frugiperda (sf-21) suspension cell culture using a recombinant baculovirus yielded approximately 2.5 mg of mitogenically fully active protein per 10(9) cells following heparin-affinity chromatography. to improve ... | 1995 | 7999789 |
| 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 ... | 1994 | 8009830 |
| 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 ... | 1994 | 8009843 |
| 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 ... | 1994 | 8009853 |
| 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 ... | 1994 | 8010671 |
| 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- ... | 1994 | 8011776 |
| 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 ... | 1994 | 8021586 |
| 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 ... | 1994 | 8021612 |