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[3h-methyl]-methionine as possible methyl donor for formation of 5'-terminus of in vitro synthesized mrna of cytoplasmic polyhedrosis virus of silkworm bombyx mori.the mrna of the cytoplasmic polyhedrosis virus of silkworm bombyx mori could be synthesized in vitro through the action of the virion associated rna-polymerase in the presence of [3h-methyl]-methionine instead of s-adenosyl-l-methionine. the 3h-mrna is isolated from the reaction mixture through a column of deae-sephadex a-25 and digested with nuclease p1 and snake venom phosphodiesterase. the results of paper electrophoresis show that the methyl group of methionine is incorporated into the 5'-te ...19817038870
relationship between structure of the 5' noncoding region of viral mrna and efficiency in the initiation step of protein synthesis in a eukaryotic system.to determine whether the rate of protein synthesis is controlled by the structure of mrna near its 5' terminus, protein-synthesizing ability, especially in its initial stage, was compared among rnas of plant viruses. those viruses used here contain several definite pieces of single-stranded rna. each of these rnas acts as a messenger. cucumber mosaic virus (cmv) rna 5 synthesizes a small amount of a protein, mr 7000, in an in vitro protein-synthesizing system from wheat germ or reticulocyte. bro ...19827041111
the double-stranded rna genome segments of cytoplasmic polyhedrosis virus are independently transcribed.the in vitro transcription of the genome segments of insect cytoplasmic polyhedrosis virus was examined for a possible mechanism of coordinate control. initiation of the first transcription cycle, primed by preincubation in the absence of ctp, was synchronous for all 10 viral genome segments. the time required for the completion of each genome transcript was proportional to the chain length, and all 10 mrna's were synthesized in molar amounts inversely proportional to their molecular weights. th ...19827045390
isolation of genome-enzyme complex from cytoplasmic polyhedrosis virus of silkworm bombyx mori.the genome-enzyme complex is isolated from the silkworm cytoplasmic polyhedrosis virus with deae-sephadex column chromatography after ultraviolet irradiation. the genome-enzyme complex shows both rna-polymerase and methyltransferase activities while using 3h-utp and [3h-methyl]-s-adenosyle-l-methionine as substrates. like the double-stranded rna genome of cpv, the genome-enzyme complex could be separated into nine segments on polyacrylamide gel electrophoresis. it is demonstrated that the rna po ...19827048527
stimulation of transcription by s-adenosyl-l-homocysteine and virion-encapsidated methyl donor in spring viraemia of carp virus.s-adenosyl-l-methionine (sam), a methyl donor, and its analogue s-adenyl-l-homocysteine (sah), an inhibitor of methylation, stimulate the activity of spring viraemia of carp virus (svcv) virion transcriptase. the stimulation observed for svcv is analogous to that observed previously (furuichi, 1974, 1978) for a totally unrelated virus, cytoplasmic polyhedrosis virus (cpv). in the absence of exogenous sam, rna with 5'-methylated termini (presumptive gpppampap) was produced, indicating that svcv h ...19817276915
a cytoplasmic polyhedrosis virus in the phlebotomine sandfly lutzomyia longipalpis. 19957787233
analysis of the c-polyhedrin genes from different geographical isolates of a type 5 cytoplasmic polyhedrosis virus.the c-polyhedrin genes of two different geographic isolates of a type 5 cytoplasmic polyhedrosis virus (cpv) were cloned. a cpv infecting orgyia pseudotsugata (opcpv), isolated in the pacific northwest of the u.s.a., and a cpv infecting heliothis armigera, isolated in south africa, were studied. both genes were found to be 883 nucleotides in length and encoded a predicted protein of 246 residues (m(r) of 28,890). comparison of the nucleotide sequences of these two viruses with another type 5 geo ...19948046399
expression in escherichia coli of the cloned polyhedrin gene of bombyx mori cytoplasmic polyhedrosis virus.cloned cdna of genomic segment 10 of bombyx mori cytoplasmic polyhedrosis virus (cpv) was placed downstream from the lambda pl promoter in expression plasmid prc23 and expressed in escherichia coli cells. a polypeptide of the same molecular weight (28 kda) as natural polyhedrin was synthesized at the level of approximately 10% of total host cell protein. this polypeptide was identified as cpv polyhedrin (r-polyhedrin) after comparative studies. the r-polyhedrin did not form any crystalline struc ...19938286955
isolation of a cytoplasmic polyhedrosis virus by physical and immunological techniques. 1975. 19938367399
expression of bombyx mori cytoplasmic polyhedrosis virus polyhedrin in insect cells by using a baculovirus expression vector, and its assembly into polyhedra.a cdna encoding the cytoplasmic polyhedrin of bombyx mori cytoplasmic polyhedrosis virus (bmcpv) strain h was introduced into an improved baculovirus expression vector which can be utilized to express foreign genes in the spodoptera frugiperda cell line iplb-sf-21ae (sf21 cells) and the b. mori cell line bmn. a recombinant virus produced large, cubic inclusion body-like structures in infected sf21 and bmn cells. western blot analysis showed that these structures were bmcpv polyhedra. this result ...19938423453
effect of mutations on the intracellular localization of bombyx mori cytoplasmic polyhedrosis virus polyhedrin.we have already cloned the polyhedrin genes of the wild-type strain h bombyx mori cytoplasmic polyhedrosis virus (bmcpv) and its mutant, strain a. in this work, polyhedrin genes of mutant bmcpv strains c1 and c2 were cloned and their nucleotide sequences were determined. the polyhedrin amino acid sequences of strains c1 and c2 were compared with that of strain h. strains c1 and c2 contained two and three sites of mutation in their polyhedrin genes, respectively. four amino acids (249rllv) were a ...19968558123
geographic distribution of cytoplasmic polyhedrosis virus infection in douglas-fir tussock moth larvae, orgyia pseudotsugata, in british columbiawe have examined the geographic distribution and prevalence of insect-specific viral infections in douglas-fir tussock moth populations in british columbia. nucleic acids extracted from field collected egg masses from 10 different locations in british columbia were subjected to agarose gel electrophoresis and southern blot analysis. electrophoresis of nucleic acids after digestion with rnase a at high and low ionic strengths showed that the extra bands detected in agarose gels were double-strand ...19968812604
sequence analysis and expression of the polyhedrin gene of choristoneura fumiferana cytoplasmic polyhedrosis virus (cfcpv).the segmented double-stranded rna genome of choristoneura fumiferana cytoplasmic polyhedrosis virus (cfcpv) was extracted, polyadenylated, reverse-transcribed into cdna and cloned. the cdna clones that hybridized to the smallest genomic segment (segment 10) were identified, and its nucleotide sequence was determined. genome segment 10 of cfcpv was found to be 1171 nucleotides in length with a single open reading frame in one strand capable of coding a predicted protein of 258 residues (mr of 29, ...19979370308
characterizations of natural and induced polyhedrin gene mutants of bombyx mori cytoplasmic polyhedrosis viruses.bombyx mori cytoplasmic polyhedrosis virus (bmcpv) polyhedrin gene from natural mutant strain b, b2 and p was cloned and the amino acid sequence was compared with that of wild-type virus (strain h). chimeric polyhedrin genes (8 types) containing only one site of mutation within the amino acid sequence were also constructed. fifteen types of polyhedrin genes were introduced into a baculovirus expression vector and hexahedral, acicular, pyramidal, or amorphous polyhedra were formed in infected cel ...19989541610
determination of the nucleotide sequence of bombyx mori cytoplasmic polyhedrosis virus segment 9 and its expression in bmn4 cells.cloning and sequencing of segment 9 of bombyx mori cytoplasmic polyhedrosis virus (bmcpv) strains h and i were performed. the segment consisted of 1,186 bp harboring 5' and 3' noncoding regions and an open reading frame from positions 75 to 1037, encoding a protein with 320 amino acids, termed ns5. comparison of the nucleotide sequences of ns5 for the two strains indicated 37 point differences resulting in only six amino acid replacements. homology search showed that ns5 has localized similariti ...19989621035
nucleotide sequence of bombyx mori cytoplasmic polyhedrosis virus segment 8.the segments 8 (s8) of the 10 double-stranded rna genomes from bombyx mori cytoplasmic polyhedrosis virus (bmcpv) strains i and h were converted into cdnas, amplified by pcr, and cloned. the nucleotide sequence analysis of the two full-length s8 cdnas showed that the segments consist of 1328 nucleotides encoding putative proteins (p44) of 390 amino acids with molecular masses of about 44 kda, which have glutamic acid-rich and proline-rich domains in their central regions. they had quite high ide ...19989657006
[cytoplasmic polyhedrosis virus and polyhedrin]. 19989752770
visualization of protein-rna interactions in cytoplasmic polyhedrosis virus.unlike the multiple-shelled organization of other reoviridae members, cytoplasmic polyhedrosis virus (cpv) has a single-shelled capsid. the three-dimensional structures of full and empty cpv by electron cryomicroscopy show identical outer shells but differ inside. the outer surface reveals a t=1 icosahedral shell decorated with spikes at its icosahedral vertices. the internal space of the empty cpv is unoccupied except for 12 mushroom-shaped densities attributed to the transcriptional enzyme com ...19999882369
two concentric protein shell structure with spikes of silkworm bombyx mori cytoplasmic polyhedrosis virus revealed by small-angle neutron scattering using the contrast variation method.the overall and internal structures of the silkworm bombyx mori cytoplasmic polyhedrosis virus was investigated by small-angle neutron scattering using the contrast variation method. data were collected in aqueous buffer solutions containing 0, 50, 75, and 100% d2o in the q range of 0.002 to 0.0774 a-1 at 5 degrees c. the radius of gyration at infinite contrast was estimated to be 336 a. the contrast matching point of the virus was determined to correspond to about 50% d2o level, evidence that t ...199910220584
the structure of a cypovirus and the functional organization of dsrna viruses.cytoplasmic polyhedrosis virus (cpv) is unique among the double-stranded rna viruses of the family reoviridae in having a single capsid layer. analysis by cryo-electron microscopy allows comparison of the single shelled cpv and orthoreovirus with the high resolution crystal structure of the inner shell of the bluetongue virus (btv) core. this suggests that the novel arrangement identified in btv, of 120 protein subunits in a so-called 't=2' organization, is a characteristic of the reoviridae and ...199910360362
stressors and rearing diseases of trichoplusia ni: evidence of vertical transmission of npv and cpv.inability to consistently rear healthy trichoplusia ni led to a study of its rearing diseases. four diseases were designated after preliminary research which included electron microscopy: cytoplasmic polyhedrosis (due to cytoplasmic polyhedrosis virus, or cpv), nuclear polyhedrosis (due to nucleopolyhedrovirus, or npv), "neonate death" syndrome (mortality in first or second instars), and "late-instar" syndrome (death in late instars accompanied by bacterial decomposition). infectious agents were ...199910486227
nucleotide sequences of genome segments 6 and 7 of bombyx mori cypovirus 1, encoding the viral structural proteins v4 and v5, respectively.nucleotide sequence analyses of cdnas derived from the double-stranded rna genome segments 6 and 7 (s6 and s7) of bombyx mori cypovirus 1 (bmcpv-1) have revealed that they consist of 1796 and 1501 nucleotides encoding putative proteins of 561 and 448 amino acids with molecular masses of 63604 and 49875 (p64 and p50), respectively. the amino acid sequence of p64, which has a high leucine residue content (10%), contains a leucine zipper motif. antiserum raised against p64 specifically bound to a v ...200010725444
"methylation-coupled" transcription by virus-associated transcriptase of cytoplasmic polyhedrosis virus containing double-stranded rna.s-adenosyl-l-methionine (sam) activated the virus-associated rna polymerase of cytoplasmic polyhedrosis virus in vitro. synthesis of single-stranded viral rna (mrna) proceeded depending on the presence of sam.a methyl residue of sam was incorporated into an rna molecule. a ribose moiety of adenylic acid in the 5'-terminal region of the nascent rna was methylated in the very early stage of the transcription. the dependence of the viral transcription on the presence of sam and the methylation of t ...197410793759
molecular characterization of bombyx mori cytoplasmic polyhedrosis virus genome segment 4.the complete nucleotide sequence of the genome segment 4 (s4) of bombyx mori cytoplasmic polyhedrosis virus (bmcpv) was determined. the 3,259-nucleotide sequence contains a single long open reading frame which spans nucleotides 14 to 3187 and which is predicted to encode a protein with a molecular mass of about 130 kda. western blot analysis showed that s4 encodes bmcpv protein vp3, which is one of the outer components of the bmcpv virion. sequence analysis of the deduced amino acid sequence of ...200111134312
nucleotide sequence of genome segment 5 from bombyx mori cypovirus 1.the complete nucleotide sequences of the double-stranded rna genome segments 5 (s5) from bombyx mori cypovirus 1 (bmcpv-1) strains i and h were determined. the segments consisted of 2,852 nucleotides encoding putative proteins of 881 amino acids with molecular masses of approximately 101 kda (p101). a homology search showed that p101 has high similarity (93%) to foot-and-mouth disease virus (fmdv) 2a protease (2apro) at amino acid position 219 to 235. these findings suggest the possibility that ...200111266213
characterization of cypovirus isolates from tropical and temperate indian saturniidae silkworms.cytoplasmic polyhedrosis virus (cypovirus, cpv) isolates from larvae of saturniidae silkworms antheraea mylitta, antheraea proylei, and antheraea assamensis were obtained and characterized. scanning electron microscopic (sem) studies revealed the presence of hexahedral (rhombic dodecahedron) polyhedral bodies of various size (1-4 microns) in individual hosts while transmission electron microscopic (tem) studies of isolated virions showed their uniform (icosahedral) shape and size (approximately ...200011332278
nucleotide sequences of segments 1, 3 and 4 of the genome of bombyx mori cypovirus 1 encoding putative capsid proteins vp1, vp3 and vp4, respectively.the complete nucleotide sequences of genomic segments s1, s3 and s4 from bombyx mori cypovirus 1 (bmcpv-1) have been determined. the segments consisted of 4190, 3846 and 3262 nucleotides encoding putative proteins of 1333, 1239 and 1058 amino acids with molecular masses of approximately 148, 140 and 120 kda (p148, p140 and p120, respectively). all segments possess a single open reading frame. homology searches showed that all three proteins have homologies to proteins of rice ragged stunt virus, ...200212029163
molecular cloning and characterization of antheraea mylitta cytoplasmic polyhedrosis virus genome segment 9.genome segment 9 of the 11-segment rna genomes of three cytoplasmic polyhedrosis virus (cpv) isolates from antheraea mylitta (amcpv), antheraea assamensis (aacpv) and antheraea proylei (apcpv) were converted to cdna, cloned and sequenced. in each case, this genome segment consists of 1473 nucleotides with one long orf of 1035 bp and encodes a protein of 345 amino acids, termed nsp38, with a molecular mass of 38 kda. secondary structure prediction showed the presence of nine alpha-helices in the ...200212029164
molecular interactions and viral stability revealed by structural analyses of chemically treated cypovirus capsids.cytoplasmic polyhedrosis virus (cpv, genus cypovirus) is a unique member of the family reoviridae which lacks the outer protective shells that exist in all other members, yet exhibits unusual stability. we have analyzed the effects of different acidic, basic, detergent, and urea treatments on cpv capsids. the integrity of the cpv capsids was unaffected under high-ph conditions that disrupted the orthoreovirus inner core, consistent with its ability to maintain structural integrity in extremely a ...200212093172
structure of cytoplasmic polyhedrosis virus from bombyx mori.the structures of full and empty capsids of cpv were studied by negative staining and electron cryomicroscopy and computer reconstruction techniques. by comparing the structures and biochemical compositions, the cpv was identified as a single-layered capsid with its five structural proteins located on it. this single capsid is arranged according to t=1 icosahedral symmetry with 12 turret-like spikes at its icosahedral vertices. the empty and full cpv show identical capsid but differ inside. the ...199912114971
structural comparisons of empty and full cytoplasmic polyhedrosis virus. protein-rna interactions and implications for endogenous rna transcription mechanism.viruses in the family reoviridae are capable of transcription within the intact capsids. as the only single-shelled and thus the simplest member of the reoviridae, cytoplasmic polyhedrosis virus (cpv) provides an attractive system for studying endogenous transcription. we report the structures of the full and empty cpv determined at 13-a resolution by electron cryomicroscopy. the structure of the empty cpv reveals a density attributed to the transcription enzyme complex, which is attached to the ...200312401805
comparison of the amino acid sequences of rna-dependent rna polymerases of cypoviruses in the family reoviridae.the nucleotide sequences of the genome segment s2 of bombyx mori cypovirus 1, s2 of lymantria dispar cypovirus 1, s1 of lymantria dispar cypovirus 14 and s1 of a proposed new electropherotype of trichoplusia ni cypovirus 15 were determined. these segments encoded putative rna-dependent rna polymerases (rdrps). the deduced amino acid sequences of rdrps within the genus cypovirus showed 32% to 94% identities, while extent of homology between rdrps in the genera cypovirus and oryzavirus, a genus mo ...200312556988
cpv, a stable and symmetrical machine for mrna synthesis.the structure of cytoplasmic polyhedrosis virus (cpv), an insect pathogen from the reoviridae family of double-strand rna viruses, has been determined at 8 a by electron cryomicroscopy and image reconstruction. it provides new information about the functions of these viral particles as stable machines for mrna synthesis.200312791245
cytoplasmic polyhedrosis virus structure at 8 a by electron cryomicroscopy: structural basis of capsid stability and mrna processing regulation.the single-shelled cytoplasmic polyhedrosis virus (cpv) is a unique member of the reoviridae. despite lacking protective outer shells, it exhibits striking capsid stability and is capable of endogenous rna transcription and processing. the 8 a three-dimensional structure of cpv by electron cryomicroscopy reveals secondary structure elements present in the capsid proteins csp, lpp, and tp, which have alpha+beta folds. the extensive nonequivalent interactions between csp and lpp, the unique csp pr ...200312791254
genomic sequence analyses of segments 1 to 6 of dendrolimus punctatus cytoplasmic polyhedrosis virus.the complete nucleotide sequences of genomic segments s1 to s6 from dendrolimus punctatus cypovirus 1 (dpcpv-1) have been determined. each segment of s1 to s6 possess a single open reading frame. conserved motifs 5' (aguaa) and 3'(guuagcc) were found at the ends of each segment. comparison of the proteins of dpcpv with those of other members in the family reoviridae lead us to suggest that s1, s3, s4 and s6 encode the viral structural protein vp1, vp2, vp3 and vp4, respectively. s5 encoded viral ...200312827465
molecular characterization of segments 7-10 of dendrolimus punctatus cytoplasmic polyhedrosis virus provides the complete genome.the nucleotide sequences of genomic segments s7-s10 from dendrolimus punctatus cypovirus strain hunan (dpcpv-hn) have been determined. this provides the complete genome sequences of dpcpv-hn. each segment of s7-s10 possess a single segment each. homology searches showed that the nucleotide sequences and the deduced amino acid sequences of dpcpv s7-10 had high level of identities with those of bombyx mori cypovirus (bmcpv) s7-10, respectively. while the amino acid sequences of the proteins encode ...200312837553
assembly into single-shelled virus-like particles by major capsid protein vp1 encoded by genome segment s1 of bombyx mori cypovirus 1.the major capsid protein vp1 encoded by genome segment s1 of bombyx mori cypovirus 1 was expressed in a baculovirus system. in the absence of any other capsid proteins, vp1 was found to assemble into single-shelled virus-like particles. the vp1 particles were more sensitive to acidic conditions than were intact particles.200312917465
on the morphology and development of insect cytoplasmic-polyhedrosis virus particles. 196514346125
entry of bombyx mori cypovirus 1 into midgut cells in vivo.in vivo entry of bombyx mori cypovirus 1 into the silkworm midgut was studied by electron microscopy of ultrathin sections of midguts from silkworm larvae that had been administered virus-contaminated leaves. in 3 h, virions were observed outside and inside midgut cells, including columnar cells, goblet cells and muscle cells. virions were seen adhering to the plasma membrane of microvilli, embedding in the membrane and settling themselves intact inside the microvilli of the columnar cells. thes ...200314700081
the use of meconia to nondestructively detect sublethal infections in heliothines (lepidoptera: noctuidae).the utility of using meconia to nondestructively detect entomopathogens of lepidopterous heliothines was examined. early-instar tobacco budworm [heliothis virescens (f.)] or cotton bollworm [helicoverpa zea (boddie)] larvae were inoculated with cytoplasmic polyhedrosis virus (cpv), serratia marcescens bizio, or nosema heliothidis lutz and splendor, and the presence of each of the entomopathogens in adults and the meconia discharged during adult eclosion was determined. as the dose of cpv occlusi ...200314994790
a 9 angstroms single particle reconstruction from ccd captured images on a 200 kv electron cryomicroscope.sub-nanometer resolution structure determination is becoming a common practice in electron cryomicroscopy of macromolecular assemblies. the data for these studies have until now been collected on photographic film. using cytoplasmic polyhedrosis virus (cpv), a previously determined structure, as a test specimen, we show the feasibility of obtaining a 9 angstroms structure from images acquired from a 4 k x 4 k gatan ccd on a 200 kv electron cryomicroscope. the match of the alpha-helices in the pr ...200415193640
molecular cloning and characterization of antheraea mylitta cytoplasmic polyhedrosis virus polyhedrin gene and its variant forms.the segments 10 (s10) of the 11 double stranded rna genomes from antheraea mylitta cytoplasmic polyhedrosis virus (amcpv) encoding a novel polyhedrin polypeptide was converted to cdna, cloned, and sequenced. three cdna clones consisting of 1502 (amcpv10-1), 1120 (amcpv10-2), and 1415 (amcpv10-3) nucleotides encoding polyhedrin of 254, 339, and 319 amino acids with molecular masses of 29, 39, and 37 kda, respectively, were obtained, and verified by northern analysis. these clones showed 70-94% se ...200515907799
fossil evidence of insect pathogens.the present report describes fossil evidence of insect pathogens, heretofore, almost non-existent, from six samples of amber ranging in age from 15 to 100 million years. they include a cytoplasmic polyhedrosis virus and trypanosomatid infection in an adult biting midge (diptera: ceratopogonidae), and a nuclear polyhedrosis virus in an adult sand fly (diptera: phlebotomidae), both from early cretaceous burmese amber, several types of fungal thalli on the cuticle of an adult mosquito (culicidae: d ...200516009374
characterization of the rna-binding domain in the dendrolimus punctatus cytoplasmic polyhedrosis virus nonstructural protein p44.dendrolimus punctatus cytoplasmic polyhedrosis virus (dpcpv-1) belongs to the cypovirus genus in the reoviridae family. the orf of genome segment 8 (s8) of dpcpv-1 was cloned into vector pmal-c2x and used to express a 44kda protein (p44) in e. coli, which was detected by western blotting. the gel mobility shift assays showed that p44 had ssrna-binding activity. competitive assay indicated that this protein only bind to ssrna and could not interact with dna and dsrna. the binding of p44 to ssrna ...200516023751
three-dimensional display and arbitrary region interactive segmentation of high-resolution virus capsids from cryo-electron microscopy single particle reconstruction.recent advances in cryo-electron microscopy (cryo-em) instrumentation and single particle reconstruction have created opportunities for high-throughput and high-resolution three-dimensional (3-d) structure determination of virus. in order to visualize and effectively understand the 3-d structure, we present a display method based on surface rendering, which has the function of 3-d arbitrary region interactive segmentation and quantitative analysis, and integrate them into a software package call ...200516186180
mapping the rna-binding domain on the dpcpv vp4.the rna-binding properties of vp4 protein of dendrolimus punctatus cytoplasmic polyhedrosis virus (dpcpv) vp4 were analyzed. vp4 was expressed in e. coli and assayed for rna binding activity by gel mobility shift assay. vp4 was found to bind rna (ssrna and dsrna) in a sequence-independent manner, but did not interact with dna. to identify the domain(s) of the protein important for rna binding, a number of deletions were made and tested by gel mobility shift assays and northwestern blot. the cent ...200616195791
[molecular cloning and sequencing of dendrolimus punctatus wenshanensis cytoplasmic polyhedrosis virus (dpwcpv) ns5 protein gene].dpwcpv were purified from infected dendrolimus punctatus wenshanensis larvae by density gradient centrifugation. the genomic dsrna segments were subsequently extracted directly from the purified polyhedra by sds treatmen, phenol/chloroform extraction and ethanol precipitation. defferent segments of genomic dsrna were separated by low melting point agarose electrophoresis, and s9 dsrna was purified after being excised from the gel. s9 rna was denaturalized in high temperature. the primers was des ...200316276867
double-stranded ribonucleic acid from cytoplasmic polyhedrosis virus of the silkworm.ribonucleic acid (rna) was extracted by phenol treatment from cytoplasmic polyhedrosis virus isolated from the midgut of infected silkworms. this rna appears as threads when precipitated in alcohol. two components having different sedimentation constants were observed. the molecular weight of the rna preparation obtained by sedimentation coefficient (weight-averaged) and intrinsic viscosity was about 2 x 10(6) to 3 x 10(6). it was one-half to one-third the size of the calculated molecular weight ...196816789087
comparison of the ribonucleic acid subunits of reovirus, cytoplasmic polyhedrosis virus, and wound tumor virus.double-stranded ribonucleic acid (rna) from intact cytoplasmic polynedrosis virus (cpv) and wound tumor virus (wtv) was analyzed by polyacrylamide gel electrophoresis. using rna from type 3 reovirus as a standard, it was calculated that cpv-rna consisted of 9 subunits corresponding to a molecular weight of 12.7 x 10(6) and wtv-rna consisted of 12 subunits corresponding to a molecular weight of 15.5 x 10(6).196916789117
characterization of a ribonucleic acid polymerase activity associated with purified cytoplasmic polyhedrosis virus of the silkworm bombyx mori.purified cytoplasmic-polyhedrosis virus has been found to have associated with it a polymerase activity capable of catalyzing the synthesis of virus-specific, single-stranded ribonucleic acid (rna) from the double-stranded rna genome.196916789118
comparison of the structure of c- and n-polyhedrins from two occluded viruses pathogenic for orgyia pseudotsugata.c-and n-polyhedrins from a cytoplasmic polyhedrosis virus (a double-stranded rna virus) and a nuclear polyhedrosis virus (a dna virus), respectively, of orgyia pseudotsugata were compared. although both polyhedrins appear to stabilize their respective virions and have similar molecular weights, they differed in amino acid composition, tryptic peptide elution profiles from a cation-exchange resin, and n-terminal amino acid sequence and showed no antigenic relatedness. this suggests that these two ...198016789195
homologous terminal sequences in the double-stranded rna genome segments of cytoplasmic polyhedrosis virus of the silkworm bombyx mori.the 3'-terminal regions (20 to 32 residues) of the genome double-stranded rna (dsrna) segments of cytoplasmic polyhedrosis virus were sequenced. the dsrnas, which were labeled at their 3' termini by incubation with [5'-(32)p]pcp and t4 rna ligase, were denatured and resolved into the plus and minus strands by agarose-urea gel electrophoresis. ten single-stranded rnas thus obtained from the five dsrna segments iv, v, viii, ix, and x were sequenced by postlabeling methods. common 3'-terminal seque ...198216789232
protein synthesis in a lymantria dispar cell line infected by cytoplasmic polyhedrosis virus.the efficiency of replication of a cytoplasmic polyhedrosis virus isolated from a member of the order lepidoptera, euxoa scandens, was studied in eight different lepidopterean cell lines. lymantria dispar cells, which were found to support viral replication, more efficiently, were used to follow the kinetics of appearance of viral-specific polypeptides by a 2-h pulse with [(35)s]methionine. five polypeptides (ca. 120,000 molecular weight [120k], 105k, 66k, 46k, and 28k) were identified as compon ...198416789251
identification of transmembrane domain of a membrane associated protein ns5 of dendrolimus punctatus cytoplasmic polyhedrosis virus.we examined the intracellular localization of ns5 protein of dendrolimus punctatus cytoplasmic polyhedrosis virus (dpcpv) by expressing ns5-gfp fusion protein and proteins from deletion mutants of ns5 in baculovirus recombinant infected insect spodoptera frugiperda (sf-9) cells. it was found that the ns5 protein was present at the plasma membrane of the cells, and that the n-terminal portion of the protein played a key role in the localization. a transmembrane region was identified to be present ...200616889685
phylogenetic analysis of heliothis armigera cytoplasmic polyhedrosis virus type 14 and a series of dwarf segments found in the genome.full-length nucleotide sequences for the genome segments (s1-s6) of heliothis armigera cytoplasmic polyhedrosis virus type 14 (hacpv-14) have been characterized. each segment consists of a single open reading frame with conserved motifs agaa and agcu at the 5' and 3' ends, respectively. comparison of the proteins of hacpv-14 with those of other members of the family reoviridae suggests that s1 encodes an rna-dependent rna polymerase (rdrp), whilst s2 encodes a major capsid protein of the virus. ...200717325373
immobilization of bioactive fibroblast growth factor-2 into cubic proteinous microcrystals (bombyx mori cypovirus polyhedra) that are insoluble in a physiological cellular environment.the supramolecular architecture of the extracellular matrix and the disposition of its specific accessory molecules give rise to variable heterotopic signaling cues for single cells. here we have described the successful occlusion of human fibroblast growth factor-2 (fgf-2) into the cubic inclusion bodies (fgf-2 polyhedra) of the bombyx mori cytoplasmic polyhedrosis virus (bmcpv). the polyhedra are proteinous cubic crystals of several microns in size that are insoluble in the extracellular milie ...200717430896
a cytoplasmic polyhedrosis virus isolated from the pine processionary caterpillar, thaumetopoea pityocampa.a cytoplasmic polyhedrosis virus (cpv) was isolated from the larvae of thaumetopoea pityocampa and shown to cause an infection of midgut cells. this viral infection revealed several important diagnostic symptoms, including discoloration of the posterior midgut, reduced feeding, and extended development time of the larvae. the virus infection is lethal to thaumetopoea pityocampa, and with the increasing doses kills the larvae within 4-5 days post infection. electron microscopy studies showed typi ...200718051275
the complete nucleotide sequence of the type 5 helicoverpa armigera cytoplasmic polyhedrosis virus genome.the s1-6, s8, and s9 segments of the type 5 helicoverpa armigera cytoplasmic polyhedrosis virus (hacpv-5, chinese strain) were cloned and sequenced, completing the hacpv-5 genome. we found that each hacpv-5 segment exhibits the conserved terminal sequences aguu and uugc located at the 5' and 3' ends, respectively. we also analyzed the translation initiation codon of the hacpv-5 genome and compared it with the available cypovirus sequences in genbank. we postulated that the conserved purine at th ...200818368473
towards atomic resolution structural determination by single-particle cryo-electron microscopy.recent advances in cryo-electron microscopy and single-particle reconstruction (collectively referred to as 'cryoem') have made it possible to determine the three-dimensional (3d) structures of several macromolecular complexes at near-atomic resolution ( approximately 3.8-4.5a). these achievements were accomplished by overcoming the challenges in sample handling, instrumentation, image processing, and model building. at near-atomic resolution, many detailed structural features can be resolved, s ...200818403197
3.88 a structure of cytoplasmic polyhedrosis virus by cryo-electron microscopy.cytoplasmic polyhedrosis virus (cpv) is unique within the reoviridae family in having a turreted single-layer capsid contained within polyhedrin inclusion bodies, yet being fully capable of cell entry and endogenous rna transcription. biochemical data have shown that the amino-terminal 79 residues of the cpv turret protein (tp) is sufficient to bring cpv or engineered proteins into the polyhedrin matrix for micro-encapsulation. here we report the three-dimensional structure of cpv at 3.88 a reso ...200818449192
transcription of double-stranded rna in cytoplasmic polyhedrosis virus in vitro.rna polymerase associated with cytoplasmic polyhedrosis virus, which contains double-stranded rna as a genome, synthesizes single-stranded rna in vitro. the rna product has the same size distribution to the genome segments, showing two fractions on a glycerol concentration gradient centrifugation. each fraction of the synthesized rna hybridized specifically with the corresponding size fraction of the denatured genome rna segments. only after the transcription has been carried out over the whole ...197318620161
subnanometer-resolution structures of the grass carp reovirus core and virion.grass carp reovirus (gcrv) is a member of the aquareovirus genus of the family reoviridae, a large family of double-stranded rna (dsrna) viruses infecting plants, insects, fishes and mammals. we report the first subnanometer-resolution three-dimensional structures of both gcrv core and virion by cryoelectron microscopy. these structures have allowed the delineation of interactions among the over 1000 molecules in this enormous macromolecular machine and a detailed comparison with other dsrna vir ...200818625243
purification and some properties of reovirus-like particles from leafhoppers and their possible involvement in wallaby ear disease of maize.reovirus-like particles, occurring in association with viroplasms, crystalline arrays and tubules, in the cytoplasm of cicadulina bimaculata capable of inducing wallaby ear disease in maize, were purified from the insects by differential centrifugation, treatment with the nonionic detergent, nonidet p-40, and sucrose density gradient centrifugation. the purified particles have a double-shelled icosahedral structure about 70 nm in diameter with external projections (a spikes) about 10 nm long loc ...198018631635
gene mapping of cytoplasmic polyhedrosis virus of silkworm by the full-length mrna prepared under optimized conditions of transcription in vitro.viral mrna synthesis by the rna polymerase associated with purified cytoplasmic polyhedrosis virus (cpv) was studied. the formation of full-length mrna products was facilitated by including in the reaction mixture 100 mm sodium acetate, high concentrations of ribonucleoside triphosphates, and proteinase k. the 10 different species of cpv mrnas were resolved into 9 discrete rna bands by agarose gel electrophoresis at ph 3.5 in buffer containing 7 m urea. each purified viral mrna hybridized specif ...198018631652
relation of the structure of cytoplasmic polyhedrosis virus and the synthesis of its messenger rna.cytoplasmic polyhedrosis virus (cpv) was observed under an electron microscope using a combination of staining and shadowing methods. projections, not only in positions horizontal to the grid but also vertical, were clearly visualized. when the particle was mildly disrupted with edta, genome dsrna was released from a projection. if the particle was previously fixed with glutaraldehyde and then disrupted, dsrna was released with a protein particle, which seemed to correspond to the base part of t ...198018631679
size determination of orgyia pseudotsugata cytoplasmic polyhedrosis virus genomic rna.molecular-weight estimates were determined for the orgyia pseudotsugata cytoplasmic polyhedrosis virus (cpv) genome. the molecular-weight estimates were obtained from measurements of glyoxal denatured rna molecules following electrophoresis in 1% agarose gels and electron micrographic contour lengths. these estimates were compared to the minimal coding capacity derived from the size of translation products of selected genomic segments. the results obtained from these different experimental appro ...198218638847
comparison of sequence diversity in several cytoplasmic polyhedrosis viruses.sequence homology among several different cytoplasmic polyhedrosis virus (cpv) types and the human reovirus (type 1) was examined by northern blot analysis and s, nuclease analysis, using random-primed cdna probes synthesized from total genomic rna. the results show no homology among the cpv type 1, bombyx mori cpv, type 5, orgyia pseudotsugata cpv, type 8, manduca sexta cpv and the human reovirus (type 1). however, there was significant homology among three type 5 cpvs, o. pseudotsugata cpv, eu ...198318639153
structural evolution of reoviridae revealed by oryzavirus in acquiring the second capsid shell.the conservation of the core structure and diversification of the external features among the turreted reoviruses appear to be relevant to structural evolution in facilitating the infection of diverse host species. the structure of rice ragged stunt virus (rrsv), in the genus oryzavirus of the family reoviridae, is determined to show a core composed of capsid shell, clamps, and long turrets. the rrsv core structure is equivalent to the core structure of orthoreovirus and the virion structure of ...200818787002
[new type of cytoplasmic polyhedrosis virus isolated from mosquitoes in china].0507bs3 virus was isolated from a mixed pool of culex sp. and anopheles sp. collected in kashi, xinjiang, china. 0507bs3 virus could cause cytopathic effects on c6/36 cells but not on vero and bhk-21 cells. viral particles had no envelope and appeared round with diameter of about 60 nm (n = 20). viral capsid was composed of a single layer and a central core. capsomeres on the surface of capsid were clearly visible. electrophoresis of viral genome showed a profile of 10 double stranded rna (dsrna ...200819226951
effects of bacillus thuringiensis toxin cry1ac and cytoplasmic polyhedrosis virus of helicoverpa armigera (hübner) (hacpv) on cotton bollworm (lepidoptera: noctuidae).in this study, interactions on the mortality and debilitating effects between cry1ac, a toxic protein produced by bacillus thuringiensis (berliner) and hacpv (chinese strain) on first and third instars larvae of helicoverpa armigera were evaluated in laboratory. when first instar was exposed to combination of bt cotton leaf discs containing hacpv (6 x 10(6), 1 x 10(7), and 3 x 10(7) pib ml(-1)) the effect on mortality was additive, when such instar larvae exposed to combination of cry1ac (0.9, 2 ...200919269293
how baculovirus polyhedra fit square pegs into round holes to robustly package viruses.natural protein crystals (polyhedra) armour certain viruses, allowing them to survive for years under hostile conditions. we have determined the structure of polyhedra of the baculovirus autographa californica multiple nucleopolyhedrovirus (acmnpv), revealing a highly symmetrical covalently cross-braced robust lattice, the subunits of which possess a flexible adaptor enabling this supra-molecular assembly to specifically entrap massive baculoviruses. inter-subunit chemical switches modulate the ...201019959989
microarray analysis of the gene expression profile in the midgut of silkworm infected with cytoplasmic polyhedrosis virus.in order to obtain an overall view on silkworm response to bombyx mori cytoplasmic polyhedrosis virus (bmcpv) infection, a microarray system comprising 22,987 oligonucluotide 70-mer probes was employed to compare differentially expressed genes in the midguts of bmcpv-infected and normal silkworm larvae. at 72 h post-inoculation, 258 genes exhibited at least 2.0-fold differences in expression level. out of these, 135 genes were up-regulated, while 123 genes were down-regulated. according to gene ...201120349281
molecular characterization of genome segment 2 encoding rna dependent rna polymerase of antheraea mylitta cytoplasmic polyhedrosis virus.genome segment 2 (s2) from antheraea mylitta cypovirus (amcpv) was converted into cdna, cloned and sequenced. s2 consisted of 3798 nucleotides with a long orf encoding a 1116 amino acid long protein (123 kda). blast and phylogenetic analysis showed 29% sequence identity and close relatedness of amcpv s2 with rna dependent rna polymerase (rdrp) of other insect cypoviruses, suggesting a common origin of all insect cypoviruses. the orf of s2 was expressed as 123 kda soluble his-tagged fusion protei ...201020488502
molecular characterization of genome segments 1 and 3 encoding two capsid proteins of antheraea mylitta cytoplasmic polyhedrosis virus.antheraea mylitta cytoplasmic polyhedrosis virus (amcpv), a cypovirus of reoviridae family, infects indian non-mulberry silkworm, antheraea mylitta, and contains 11 segmented double stranded rna (s1-s11) in its genome. some of its genome segments (s2 and s6-s11) have been previously characterized but genome segments encoding viral capsid have not been characterized.201020684765
atomic model of a cypovirus built from cryo-em structure provides insight into the mechanism of mrna capping.the cytoplasmic polyhedrosis virus (cpv) from the family reoviridae belongs to a subgroup of "turreted" reoviruses, in which the mrna capping activity occurs in a pentameric turret. we report a full atomic model of cpv built from a 3d density map obtained using cryoelectron microscopy. the image data for the 3d reconstruction were acquired exclusively from a ccd camera. our structure shows that the enzymatic domains of the pentameric turret of cpv are topologically conserved and that there are f ...201121220303
electron tomography reveals polyhedrin binding and existence of both empty and full cytoplasmic polyhedrosis virus particles inside infectious polyhedra.previous studies have described the structure of purified cytoplasmic polyhedrosis virus (cpv) and that of polyhedrin protein. however, how polyhedrin molecules embed cpv particles inside infectious polyhedra is not known. by using electron tomography, we show that cpv particles are occluded within the polyhedrin crystalline lattice with a random spatial distribution and interact with the polyhedrin protein through the a-spike rather than as previously thought through the b-spike. furthermore, b ...201121471233
atomic model of cpv reveals the mechanism used by this single-shelled virus to economically carry out functions conserved in multishelled reoviruses.unlike the multishelled viruses in the reoviridae, cytoplasmic polyhedrosis virus (cpv) is single shelled, yet stable and fully capable of carrying out functions conserved within reoviridae. here, we report a 3.1 å resolution cryo electron microscopy structure of cpv and derive its atomic model, consisting of 60 turret proteins (tps), 120 each of capsid shell proteins (csps) and large protrusion proteins (lpps). two unique segments of csp contribute to cpv's stability: an inserted protrusion dom ...201121565700
a fast mapping method in the isaf reconstruction algorithm.isaf (icosahedral symmetry-adapted functions) algorithm is the new high-resolution algorithm of icosahedral molecules. but its running speed is very slow because of the time-consuming operations of mapping sampling points into 3d space. in this paper, a fast mapping method is proposed to increase the running speed of this stage. first of all, the angle corresponding to one pixel arc in the maximum fourier ring was taken as the sampling angle and the same angle sampling was applied in every rings ...201122255199
high-speed fixed-target serial virus crystallography.we report a method for serial x-ray crystallography at x-ray free-electron lasers (xfels), which allows for full use of the current 120-hz repetition rate of the linear coherent light source (lcls). using a micropatterned silicon chip in combination with the high-speed roadrunner goniometer for sample delivery, we were able to determine the crystal structures of the picornavirus bovine enterovirus 2 (bev2) and the cytoplasmic polyhedrosis virus type 18 polyhedrin, with total data collection time ...201728628129
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