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in vitro and in vivo expression of rubella virus glycoprotein e2: the signal peptide is contained in the c-terminal region of capsid protein.the 24 subgenomic mrna of rubella virus (rv) specifies a polyprotein which is post-translationally processed to three structural protein species e1, e2, and capsid. e1 and e2 are membrane glycoproteins forming the virion spikes. in the polyprotein, e2 and e1 are both preceded by stretches of uncharged, mainly nonpolar amino acids which probably function as signal peptides mediating translocation into the endoplasmic reticulum. we have previously shown that translocation of e1 is reinitiated by a ...19892683361
detection of rubella virus antigen by one-step time-resolved fluoroimmunoassay and by enzyme immunoassay.a one-step time-resolved fluoroimmunoassay (tr-fia) and a conventional two-step enzyme immunoassay (eia) for the detection of rubella virus antigen were developed. two noncompetitive mouse monoclonal antibodies reactive with epitopes on the e1 polypeptide of rubella virus served as immunoreagents. one of the monoclones (7a6) was used for coating the solid phase, and the other (2c3) was labeled with either europium chelate or with horseradish peroxidase. for tr-fia, the specimen was incubated sim ...19892693609
low ph-dependent sindbis virus-induced fusion of bhk cells: differences between strains correlate with amino acid changes in the e1 glycoprotein.expression of alphavirus glycoproteins on the surface of infected cells leads to cell fusion after exposure to acidic ph. two strains of sindbis virus, ar339 (sv) and neuroadapted sindbis virus (nsv), which differ in virulence for weanling mice, were found to differ in ph-dependent fusion. bhk-21 cells infected with sv fused maximally after shifting to ph 5.4, whereas cells infected with nsv required a lower ph, ph 4.8, for maximal fusion. no difference was noted in the optimal ph for agglutinat ...19892705310
intracellular transport and processing of sindbis virus glycoproteins.the intracellular transport and processing of sindbis virus envelope glycoproteins were studied in cells infected with sindbis virus using the mannose-specific enzyme, endoglycosidase h (endo h). in pulse/chase labeling experiments of hamster cells with [35s]methionine, sindbis glycoproteins pe2 and e1 became endo h resistant in two steps at 12.5 and 20.0 min after a 5-min pulse, suggesting that the glycoproteins required this period of time to be transported to the golgi compartments containing ...19892718376
[use of probes containing cloned genes of the karelian fever virus in detecting viral genetic material in infected cells by a molecular hybridization method].two plasmid dna-probes containing dna-replicas of kfv genes (clone 1-protein e1 gene, clone 9--proteins e1 and p1 genes of kfv) were used for detection of the genetic material of karelian fever virus (kfv) in the infected cells and study of the time course of accumulation of virus-specific rnas in the process of infection. the detection was performed by the method of rna:dna dot-hybridization. both probes were hybridized with kfv and sindbis virus rna in equal amounts--5 x 10(2) infected cells a ...19892728408
nucleotide sequence of capsid, e2 and e1 protein genes of rubella virus vaccine strain ra27/3. 19892740235
sindbis virus ts103 has a mutation in glycoprotein e2 that leads to defective assembly of virions.sindbis virus mutant ts103 is aberrant in the assembly of virus particles. during virus budding, proper nucleocapsid-glycoprotein interactions fail to occur such that particles containing many nucleocapsids are formed, and the final yield of virus is low. we have determined that a mutation in the external domain of glycoprotein e2, ala-344----val, is the change that leads to this phenotype. mapping was done by making recombinant viruses between ts103 and a parental strain of the virus, using a f ...19892746736
immune responses to wild and vaccine rubella viruses after rubella vaccination.antibody responses to individual structural proteins (e1, e2, and c) of the m33 wild rubella virus and the ra 27/3 live attenuated rubella strain were assayed by immunoblotting in 11 girls, following immunization with ra 27/3 rubella vaccine. serum samples were drawn before immunization and at 10 days, 1 month, 1 year, 2 years, and 3 years afterwards. all the subjects showed antibodies to e1 glycoprotein of both the virus strains up to three years after immunization, indicating the importance of ...19892764728
intracellular synthesis and processing of the structural glycoproteins of turkey enteric coronavirus.pulse labeling of cells with [35s]methionine or [3h]glucosamine at different times after infection, followed by sds-page and western immunoblotting analysis using rabbit anti-tcv hyperimmune serum, was used to resolve and identify tcv-induced intracellular proteins. the viral structural proteins (gp 200, gp 140/gp 66, gp 100/gp 120, p 52, and gp 24/p 20) were detected in radiolabeled cell extracts by 9 to 12 hours post-infection, as well as two possible non-structural proteins with apparent mol. ...19892774975
biosynthesis, membrane translocation, and surface expression of sindbis virus e1 glycoprotein.sindbis virus glycoproteins pe2 (precursor of e2) and e1 are coded in this order by the same monocistronic mrna, cotranslationally inserted in the endoplasmic reticulum membrane and then transported to the cell surface where the progeny virus is released by budding. in the virion, three e1 plus three e2 molecules form hexameric spike complexes. previous work (s. bonatti, g. migliaccio, g. blobel, and p. walter (1984), eur. j. biochem. 140, 499-502) revealed a single signal sequence for cotransla ...19892806407
[monoclonal antibodies to the karelian fever virus. the characteristics of their biological properties].biological properties of 6 variants of monoclonal antibodies (mab) to karelian fever virus, a member of the alpha-virus serocomplex sindbis-wee, produced by the available hybridomas. the productivity of hybridomas of the "karel" series in tissue culture and in cultivation as ascitic fluid was evaluated. among the antibodies analysed, all were specific to envelope proteins, of them 2 were against protein e2 and four against protein e1. comparison of mca biologic activity (neutralizing, antihemagg ...19901979458
characterization and reactivity of monoclonal antibodies to the miller strain of transmissible gastroenteritis virus of swine.hybridomas secreting monoclonal (mab) to transmissible gastroenteritis virus (tgev) were produced by fusion of sp2/0 myeloma cells and splenic lymphocytes of balb/c mice immunized with the virulent cell-passaged miller strain of tgev. the mab secreted by these hybridomas were partially characterized; 4 of them (ma4, ma5, mh11, mb2) had high-neutralization titer for tgev. the remaining 7 (mc6, md9, me5, mg5, mf2, me9, mg7) did not neutralize tgev at 1:25 dilution. all 4 neutralizing and 2 of the ...19901689128
pathogenesis of encephalitis induced in newborn mice by virulent and avirulent strains of sindbis virus.strains of sindbis virus differ in their virulence for mice of different ages; this variation is related in large part to variations in the amino acid compositions of e1 and e2, the surface glycoproteins. the comparative pathogenesis of sindbis virus strains which are virulent or avirulent for newborn mice has not been previously examined. we have studied the diseases caused by a virulent wild-type strain, ar339, and two less virulent laboratory strains, toto1101 and hrsp (hr small plaque). afte ...19901691310
a monoclonal antibody to ly-6 gene product inhibits generation of functionally active t cells and recognizes single antigenic specificity whose expression is up-regulated in virus-transformed rat fibroblast.in order to elucidate the relationship between the structure and function of proteins encoded for by the ly-6 gene complex, a cdna was constructed for a ly-6.2 specificity and then monoclonal antibodies (mab) generated to bacterially synthesized protein. the addition of one of these mab, designated pb-19, inhibited the proliferative response of t cells to concanavalin a (con a) or major histocompatability complex (mhc) alloantigens. reactivity of pb-19 to the ly-6 specificity was blocked by a kn ...19901692303
studies on the role of linear epitopes in neutralization of alphaviruses.by using three synthetic peptides (16-19 amino acids in length) representing different regions of glycoproteins e1 (peptide 3) and e2 (peptides 1 and 2) of sindbis and semliki forest virus and isolated glycoprotein fractions of both viruses in reduced and non-reduced form, the role of linear epitopes for the neutralization was investigated. the reaction patterns of sera induced by immunization with these antigens indicate that conformational epitopes do play the major role in neutralization of a ...19901694615
a conformational change in sindbis virus glycoproteins e1 and e2 is detected at the plasma membrane as a consequence of early virus-cell interaction.a conformational change in the structure of sindbis (sb) virus was detected after virion attachment to baby hamster kidney cells but before internalization. the alteration was manifested as increased virion binding of certain glycoprotein e1 and e2 monoclonal antibodies (mabs) that recognized transitional epitopes. these epitopes were inaccessible to mab on native virions but became accessible to their cognate mabs in the early stages of infection. transit of virions through a low-ph compartment ...19901695253
variants of venezuelan equine encephalitis virus that resist neutralization define a domain of the e2 glycoprotein.stable neutralization (n) escape variants of venezuelan equine encephalitis (vee) virus were selected by anti-e2 glycoprotein monoclonal antibodies (mabs) that neutralize viral infectivity, block viral hemagglutination, and passively protect mice. the nucleotide sequence of the e1, e2, and e3 genes of four variants revealed a clustering of single mutations in a domain spanning e2-182 to e2-207. the conformation of this short linear sequence affects antigenicity in the n domain because reduction ...19901695412
[monoclonal antibodies cross-reacting with the tick-borne encephalitis virus and with the venezuelan equine encephalomyelitis virus].employment of radioimmunoassay led to the demonstration of serological crossing between tick-borne encephalitis (tbe) virus and venezuelan equine encephalomyelitis (vee) virus. using hybridoma technology, three hybridomas were produced secreting monoclonal antibodies (mab) cross-reacting with these two viruses. with mab, the epitope of binding of these antibodies was shown to be located on protein e of tbe virus and protein e1 of vee virus. despite the low percentage (14%) of homology of amino a ...19901699359
molecular characterization of the 229e strain of human coronavirus.human coronaviruses (hcv) cause various respiratory, gastrointestinal and possibly neurological disorders. very little is known of the molecular biology of these ubiquitous pathogens. we have undertaken the molecular characterization of the prototype 229e strain of hcv. the virus grew to the highest titers on a human embryonic lung cell line (l132) at 33 degrees c and purification was optimal on renografin-60 gradients. metabolic labeling with [35s]methionine or [3h]glucosamine or galactose and ...19902103105
brefeldin a arrests the intracellular transport of viral envelope proteins in primary cultured rat hepatocytes and hepg2 cells.we have studied the effect of brefeldin a (bfa) on the intracellular transport of the envelope proteins of vesicular stomatitis virus (vsv) and sindbis virus in primary cultured rat hepatocytes. bfa (2.5 micrograms/ml) inhibited not only the secretion of plasma proteins into the medium, but also the assembly of both g protein of vsv and e1 and e2 proteins (envelope proteins) of sindbis virus into respective virions. concomitantly, both the acquisition of endo-beta-n-acetylglucosaminidase h resis ...19902105715
processing and intracellular transport of rubella virus structural proteins in cos cells.plasmids encoding rubella virus (rv) structural proteins c-e2-e1, e2-e1, e2, and e1 have been constructed in the eukaryotic expression vector pcmv5. the processing and intracellular transport of these proteins have been examined by transient expression of the cdnas in cos cells. compared to alphaviruses, processing of rv glycoprotein moieties occurred relatively slowly and the transport of glycoproteins e2 and e1 to the plasma membrane was inefficient. indirect immunofluorescence revealed that t ...19902117827
biosynthesis, maturation, and acid activation of the semliki forest virus fusion protein.the semliki forest virus spike protein has a potent membrane fusion activity which is activated in vivo by the low ph of endocytic vacuoles. the spike protein is composed of two transmembrane subunits, e1 and e2, plus e3, a peripheral polypeptide. acid-induced conformational changes in the e1 or e2 subunits were analyzed by using monoclonal antibodies specific for the acid-treated spike protein. e1 and e2 reacted with the antibodies after treatment of wild-type or mutant virus at the ph of fusio ...19902118964
efficacy of cytotoxic t lymphocytes against virus-induced tumors.cytotoxic t lymphocytes (ctls) against virus-induced tumors are highly effective mediators of tumor-specific immunity in vivo. ctls bearing the surface molecule cd8 recognize small (approximately 10-amino-acid) viral peptides that are presented in association with major histocompatibility (mhc) class i molecules at the surface of tumor cells. in the case of mouse tumors induced by the early region (e1) of human adeno-virus type 5 (ad5), cloned cd8+ ctls directed against a peptide derived from th ...19902143919
enteric adenovirus type 40: expression of e1b mrna and proteins in permissive and nonpermissive cells.the enteric adenovirus type 40 (strain dugan) grows well in tissue culture only when the e1b 55k protein of ad5 or ad12 is supplied in trans, either constitutively expressed in an established cell line or by coinfection with an appropriate helper virus (v. mautner, n. mackay, and v. steinthorsdottir, 1989, virology 171, 619-622). the synthesis of ad40 e1b mrnas and proteins has been examined under permissive and nonpermissive conditions: at late times postinfection in permissive cells, e1b-speci ...19902145689
cold recombinant influenza b/texas/1/84 vaccine virus (crb 87): attenuation, immunogenicity, and efficacy against homotypic challenge.healthy susceptible young adults were inoculated intranasally with increasing doses of wild-type influenza b/texas/1/84, or the cold-adapted vaccine possessing the genes specifying the hemagglutinin and neuraminidase of the wild-type parent and the six internal genes of cold adapted b/ann arbor/1/66 (crb 87). most volunteers inoculated with 10(6.6)-10(7.6) tcid50 of crb 87 were infected, but a high frequency of serum antibody responses was seen only at the highest dose (17/29; 59%). the dose of ...19902153185
variable requirements for herpes simplex virus immediate-early proteins in the expression of the adenovirus e2 gene.regulation of the adenovirus e2 gene by trans-activating proteins encoded by herpes simplex virus was investigated. coinfection of vero cells was performed with ad5 dl312 (an e1 deletion mutant) and either wildtype hsv, mutant virus encoding a temperature-sensitive icp4 protein (tsk), or mutants carrying deletions in the icp4 (d120) or icp0 (dl x 3.1) gene. as detected by the presence of e2 mrna, or the product of the e2 gene, 72-kda dna binding protein (dbp), functional icp4 was sufficient for ...19902155517
resistance of human cells to the adenovirus e3 effect on class i mhc antigen expression. implications for antiviral immunity.group c human adenovirus (ad) serotypes (e.g., ad2 and ad5) cause persistent infections in man. one proposed mechanisms to explain human adenovirus persistence is an ineffective ctl response due to reduced cell surface expression of class i mhc ag on virally infected cells, an effect mediated by the 19-kda glycoprotein encoded by ad early region 3 (e3). in the present study, the generality of this phenomenon was tested by analyzing e3 19-kda glycoprotein down-regulation of cell surface class 1 m ...19902156934
expression of the human papillomavirus type 16 genome in sk-v cells, a line derived from a vulvar intraepithelial neoplasia.the sk-v cells, established from a premalignant vulvar lesion, contain human papillomavirus type 16 (hpv-16) sequences integrated at a single cellular site and derive from a cell clone present in vivo. transcription of the hpv-16 genome in sk-v cells was analysed by cdna heteroduplex mapping and sequencing, and by rnase mapping. viral sequences were shown to be transcribed into virus-cell fusion messengers. the two major transcripts have a coding capacity for a truncated e6 protein, an e7 protei ...19902157796
integrated hpv 1 genomes in a human keratinocyte cell line can be transactivated by a sv40/bpv1 recombinant virus which expresses bpv1 e2 proteins.this paper describes studies carried out on an hpv 1 carrying human keratinocyte cell line (svd2) and two subclones of it. although these lines contain multiple copies of hpv 1 genomes, in situ hybridization revealed that integration was restricted to band q33 on the long arms of chromosome 2. an e4 1.25-kb mrna was specifically identified by northern blotting and a pcr generated cdna confirmed the presence of the e1/e4 spliced mrna which is abundant in hpv 1 containing papillomas. infection of ...19902158183
characterization of multiple molecular interactions between human cytomegalovirus (hcmv) and human immunodeficiency virus type 1 (hiv-1).in transient gene expression assays we observed an increase in expression of the bacterial chloramphenicol acetyl-transferase (cat) gene, under the transcriptional control of the hiv-1 ltr (pltr-cat), when this plasmid was cotransfected into vero or mrc-5 cells with a plasmid containing either the hcmv immediate early 1 and 2 (e1, ie2) genes (prl43a) or just the ie2 gene (pmp18). when the hcmv ie1 gene (pmp12) was cotransfected with pltr-cat into vero cells the level of measurable cat gene activ ...19902158700
identification of monoclonal antibodies capable of differentiating antigenic varieties of eastern equine encephalitis viruses.we have isolated and characterized 3 monoclonal antibody (mab) reagents useful in the serological identification of varieties of eastern equine encephalitis (eee) viruses. these antibodies were specific for the e1 glycoprotein of their homologous viruses. one mab, 1b5c-3, reacted specifically with all north american (na) eee viruses isolated over a 50 year period. this antigenic stability of na isolates was genetically confirmed by oligonucleotide fingerprinting. evolutionary stability is a uniq ...19902158755
a major transcript of human papillomavirus type 16 in transformed nih 3t3 cells contains polycistronic mrna encoding e7, e5, and e1--e4 fusion gene.we have cloned cdna of the major 1.8 kb mrna from hpv 16-transformed nih 3t3 cells (pm3t3). the entire nucleotide sequences of this cdna were determined and compared with prototype hpv 16 genomic dna sequences. the 5'-end of the cdna was flanked by approximately 300 bp of cellular sequences, and the 3'-end of the cdna sequences contained poly a residues following at nt 4230. hpv 16 sequences began at nt 124, downstream of a major viral p97 promoter, within the e6 open reading frame (orf). the fi ...19902161158
molecular cloning and nucleotide sequence of hog cholera virus strain brescia and mapping of the genomic region encoding envelope protein e1.genomic rna of hog cholera virus (hcv) strain brescia was cloned and sequenced. the nucleotide sequence was deduced from overlapping cdna clones and comprises 12,283 nucleotides. we cloned the complete 3' end of the hcv genome, but could not unequivocally prove that the cdna sequence also completely covers hcv rna at the 5' end. the hcv genome contained one large open reading frame, which spans the viral plus strand rna and encodes an amino acid sequence of 3898 residues with a calculated molecu ...19902162104
vaccinia recombinants expressing early bovine papilloma virus (bpv1) proteins: retardation of bpv1 tumour development.papillomaviruses are aetiological agents of epithelial proliferative diseases in animals and in man. it was previously demonstrated that animals inoculated with live vaccinia recombinants expressing early proteins of polyoma virus resist challenge with polyoma-tumour cells, and this approach has been extended to the development of a vaccine against papillomavirus-transformed cells. bovine papillomavirus type 1 (bpv1), a virus responsible for dermal lesions in cattle, is a prototype virus of the ...19902163573
diagnostic complementary dna probes for genome segments 2 and 3 of epizootic hemorrhagic disease virus serotype 1.potential diagnostic complementary dna (cdna) clones of gene segments 2 and 3 from epizootic hemorrhagic disease virus serotype 1 (ehdv-1) have been produced. individual segments of ehdv-1 were isolated, denatured with methylmercury hydroxide, and polyadenylated. the polyadenylated rna was reverse-transcribed and self-hybridized into duplex structures, and the incomplete ends were repaired. the resulting product was then cloned into the plasmid vector pbr322, using the complementary tailing meth ...19902164331
lysosomal sorting mutants of coronavirus e1 protein, a golgi membrane protein.as a model for the intracellular sorting of golgi membrane proteins, we are studying the e1 protein of the coronavirus mouse hepatitis virus a59. the wild-type protein, when expressed from synthetic rna, is localised in the golgi complex. when the second and third of the three predicted membrane-spanning sequences were deleted from the protein, the resulting mutant was retained in the endoplasmic reticulum. in contrast, removal of the first and second membrane-spanning sequences allowed the prot ...19902164517
human papillomavirus type 16 dna expresses a replication modulation factor in cos-1 cells.plasmid dna including the simian virus 40 (sv40) origin of replication undergoes uncontrolled, runaway replication in cos-1 cells owing to the intracellular production of sv40 large t antigen. covalent linkage of such plasmids with human papillomavirus type 16 (hpv-16) dna was found to prevent runaway replication. replication control was found to be dependent on the presence of hpv-16 dna sequences including the e1 open reading frame and part of the non-coding region.19902167937
identification of a 68-kilodalton nuclear atp-binding phosphoprotein encoded by bovine papillomavirus type 1.e1 is the largest open reading frame (orf) of bovine papillomavirus type 1 (bpv-1) and is highly conserved among all papillomaviruses, maintaining its size, amino acid composition, and location in the viral genome with respect to other early genes. multiple viral replication functions have been mapped to the e1 orf of bpv-1, and evidence suggested that more than one protein was encoded by this orf. we previously identified a small protein (m) whose gene consists of two exons, one encoded by the ...19902168988
molecular biology of transmissible gastroenteritis virus.the causative agent (tgev) of porcine transmissible gastroenteritis belongs to the coronaviridae, a family of enveloped viruses with a positive, single-stranded rna genome. important progress has recently been made concerning the molecular biology of tgev. the research work of our group has been focused on two main aspects: genome structure and functional domains of the envelope proteins. tgev genomic rna is organised into seven regions. the sequence of six of them, i.e. the 3' most 8300 nucleot ...19902169670
proteins encoded by the bovine papillomavirus e1 open reading frame: expression in heterologous systems and in virally transformed cells.the e1 open reading frame (orf) of bovine papillomavirus type 1 is required for the persistence of viral genomes as multicopy plasmid molecules in transformed rodent fibroblasts. e1 has been reported to contain two separate complementation groups (m and r, corresponding to n- and c-terminal domains, respectively) which regulate viral replication. however, e1 behaves as a single gene with respect to cell transformation and viral transcription. we examined the proteins translated from the entire o ...19902173778
[a comparative analysis of the polypeptides of the the sindbis and karelian fever viruses].in pulse-chase experiments with karelian fever virus-infected cells, proteins were found with molecular weights of 130, 98, 78, and 62 kd of which the first, second and fourth were classified as polypeptide precursors of the structural proteins of virion. the molecular weights of proteins e1, e2 and c of 52, 47 and 34 kd, respectively, as well as isoelectric points of isolated glycoproteins (pi e1 = 6.3, pi e2 = 8.4) were similar in kfv (strain leiv-9298) and sindbis virus (strain ar339). the an ...19902176422
analysis of properties of monoclonal antibodies to transmissible gastroenteritis virus using to-163 strain.nineteen monoclonal antibodies (mabs), reactive in enzyme-linked immunosorbent assay (elisa), with porcine transmissible gastroenteritis (tge) virus to-163 were obtained. of these mabs, 5 showed neutralizing (nt) activity (x 3,200 to 25,600) against to-163. one of the mabs which had nt activity showed hemagglutination inhibition activity (x 5,120) too. 14 hybridomas of polypeptide specificity against to-163 strain were developed from which 11, 2, and 1 were specific for protein e2, n, and e1, re ...19902176427
function of semliki forest virus e3 peptide in virus assembly: replacement of e3 with an artificial signal peptide abolishes spike heterodimerization and surface expression of e1.the semliki forest virus spike glycoproteins e1 and p62 form a heterodimeric complex in the endoplasmic reticulum (er) and are transported as such to the cell surface. in the mature virus particle, the heterodimeric association of e1 and e2 (the cleavage product of p62) is maintained, but as a more labile and acid-sensitive oligomer than the e1-p62 complex. the e3 peptide forms the n-terminal part of the p62 precursor and carries the signal for the translocation of p62 into the lumen of the er. ...19902200886
a single amino acid change in e3 of ts1 mutant inhibits the intracellular transport of sfv envelope protein complex.at 39 degrees the envelope protein complex (e1-p62) of semliki forest virus mutant ts1 is arrested in the rough endoplasmic reticulum (rer). when the infected cultures are shifted to 28 degrees, the complex is transported to the cell surface. during the transport p62 is cleaved into e2 under conditions in which no virus budding takes place. we have sequenced the cdna, which encodes the envelope proteins of ts1. comparison with the respective wild-type nucleotide sequence shows only one nucleotid ...19902238466
semliki forest virus induced cell-cell fusion at neutral extracellular ph.semliki forest virus-induced cell-cell fusion from within was considered to exclusively occur at mildly acidic ph (less than 6.2). data of this study show that such cell fusion can also be triggered by transient acidification of the cytoplasm of infected cells at an extracellular, neutral ph. results were obtained by utilizing nh4cl pulses combined with covalent modification of cell surface proteins. the observation implies a revision of the current consensus regarding the mechanism of semliki f ...19902249002
cloning & expression of chikungunya virus genes coding structural proteins in escherichia coli.dna complementary to the single stranded rna genome of chikungunya (chik) virus with poly a tract was cloned into the plasmid pgem-3zf(-) and 5zf(+) by blunt end ligation strategy. clones containing the cdna inserts were selected by x-gal, iptg system. they were tested for the expression of structural protein(s) of chik virus by in situ enzyme immunoassay and western blot. the former assay system showed the presence of expressed viral proteins. analysis of western blot shows that three structura ...19902269513
translocation and cleavage of rubella virus envelope glycoproteins: identification and role of the e2 signal sequence.the structural proteins of rubella virus (rv) are translated as a large polyprotein precursor, p110, which is processed to produce the mature virion components, the 33k capsid protein (c) and the two envelope glycoproteins, e1 (58k) and e2 (42k to 47k). the precise processing mechanism has not been elucidated; however it must include at least two proteolytic cleavages to release the individual virion components from the polyprotein, and it must provide for their dichotomous intracellular distrib ...19902273395
clofibrate-inducible rat hepatic p450s iva1 and iva3 catalyze the omega- and (omega-1)-hydroxylation of fatty acids and the omega-hydroxylation of prostaglandins e1 and f2 alpha.cytochromes p450iva1 and iva3 display 72% amino acid sequence similarity and are expressed in livers of rats treated with the hypolipidemic drug clofibrate. the catalytic activities of iva1 and iva3 were examined by cdna-directed expression using vaccinia virus. cdna-expressed iva1 and iva3 had relative mrs of 51,500 and 52,000, respectively, on sds-polyacrylamide gels. both enzymes displayed reduced, co-bound absorption spectra with lambda max of 452.5 nm. iva1 and iva3 hydroxylated lauric acid ...19902280187
differential growth of human enteric adenovirus 41 (tak) in continuous cell lines.differing reports exist about the replication of human enteric adenoviruses (enads) in various cell lines. there was a suggestion that enads are defective, do not grow on primary human diploid cells, and behave like ad host-range mutants, i.e., they require early gene products from other ad types for efficient growth. thus, initially the graham-293 cell line, which contains the e1 region (e1a, e1b) of ad5, was thought to be an ideal host for enads, because it provided the needed functions. our f ...19902294640
intracellular processing, glycosylation, and cell-surface expression of the measles virus fusion protein (f) encoded by a recombinant adenovirus.the membrane fusion protein of measles virus (mvf) is a surface glycoprotein which is essential for initiation of viral infection. the f protein mediates penetration of the host cell through a process of membrane fusion between the viral envelope and the host cell plasma membrane. to study the structure-function relationship of the mvf protein, a recombinant adenovirus, ad5mvf, was constructed which expressed the f protein in mammalian cells. the mvf gene was inserted into the ad5 genome by homo ...19902309445
immunoaffinity purification and characterization of the envelope protein e1 of hog cholera virus.the envelope protein e1 of hog cholera virus (hcv) was isolated by immunoaffinity purification with monoclonal antibodies (mabs) directed against hcv. e1 consisted of a doublet of glycoproteins which varied in size from 51k to 56k between the three strains tested. e1 contains major antigenic determinants of hcv which are conserved, and are involved in neutralization by mabs. in infected cells, e1 was found always connected with a glycoprotein of 31k. when n-linked glycans were removed, e1 had a ...19902313266
the cleavage of p62, the precursor of e2 and e3, is an early and continuous event in semliki forest virus-infected aedes albopictus cells.the cleavage of p62 of semliki forest virus (sfv) in c6/36 (aedes albopictus) cells was investigated by pulse-chase labeling experiments and analysis of the sugar side chain of e1 using endoglycosidases. similar to vertebrates, e1, e2, and p62 are transported as complexes in c6/36 cells. this observation allows the use of e1 as a positional marker for the transport and processing of e2 and p62. the oligosaccharide on the viral spike e1 protein was modified first to an endo-d-sensitive (35 min) a ...19902317152
chromosomal damage induced by human adenovirus type 12 requires expression of the e1b 55-kilodalton viral protein.infection of human embryonic kidney cells with adenovirus type 12 results in the induction of damage at specific (17q21-22, 1p36, 1q21, and 1q42-43) and random sites in the cellular chromosomes. a previous study by durnam et al. (d. m. durnam, p. p. smith, j. c. menninger, and j. k. mcdougall, cancer cells 4:349-354, 1986) indicated that the expression of viral early region 1 (e1) is sufficient for the induction of damage at band 17q21-22. in the present report we used an adenovirus type 12-aden ...19902325204
[detection of structural proteins in rubella virus using immunoblotting].in partially purified virus preparations the structure proteins e1, e2 and c of rubella virus were demonstrated by immunoblotting using human sera. first tests analyse the igg immune response by immunoblotting. possibilities are discussed for the application of this method in diagnosis.19902336854
antibody response to rubella virus structural proteins in multiple sclerosis.the antibody response to the structural proteins of rubella virus was studied in patients with multiple sclerosis (ms). irrespective of the antibody titer to whole rubella virus, the relative proportion of the igg response to the surface glycoprotein e1 was diminished, and that to the surface glycoprotein e2 was elevated in ms patients when compared to a matched control population of normal health individuals or a group of patients with systemic lupus erythematosus and other collagen vascular di ...19902360794
detection of bovine enteric coronavirus in clinical specimens by hybridization with cdna probes.molecular hybridization, previously optimized for purified bovine coronavirus (bcv), was adapted for detection of virus in clinical specimens. for this purpose, the accuracy of the existing tests had to be improved and suitable means for removal of extraneous molecules had to be established. six radioactive probes were used to obtain adequate detection signals. these probes, containing the complete n and e1 gene sequences and other sequences, hybridized to about 1/4 of the total length of the vi ...19902366761
attenuating mutations in glycoproteins e1 and e2 of sindbis virus produce a highly attenuated strain when combined in vitro.alterations in either the e1 or the e2 glycoprotein of sindbis virus can affect pathogenesis in animals. previously, we identified two distinct e1 glycoprotein gene sequences which differed in their effect on pathogenesis. one had an attenuation phenotype following subcutaneous inoculation of neonatal mice (e1 ala-72, gly-75, and ser-237), while the other was virulent (e1 val-72, asp-75, and ala-237). in this study, we examined the basis for this difference in pathogenesis by using a full-length ...19902384921
spike protein oligomerization control of semliki forest virus fusion.we have recently shown, using cleavage-deficient mutants of the p62-e1 membrane protein complex of semliki forest virus that p62 cleavage to e2 is necessary for the activation of the fusion function of the complex at ph 5.8 (a ph optimal for virus fusion) (m. lobigs and h. garoff, j. virol. 64:1233-1240, 1990). in this study, we show that the mutant precursor complexes can be induced to activate membrane fusion when treated with more acidic buffers (ph 5.0 and 4.5), which also appear to dissocia ...19902398543
the sindbis virus 6k protein can be detected in virions and is acylated with fatty acids.a small hydrophobic polypeptide is encoded within the genome of the alphaviruses by a set of 165 nucleotides which map between the sequences for the two virus glycoproteins. this polypeptide has been referred to as 6k and was previously found on membranes in virus-infected cells. we report here that this protein is heavily acylated with long chain fatty acids covalently attached in hydroxylamine-sensitive ester bonds and that the 6k protein can be detected in purified preparations of virions. a ...19902408229
the e1 functional epitope of the human interferon gamma is a nuclear targeting signal-like element. mapping of the e1 epitope.eight neutralizing monoclonal antibodies (mabs) directed against the human interferon gamma (huifn-gamma) that were classified in the e1 epitope group were mapped by the synthetic peptide approach. a set of 136 octapeptide homologs of the 143-residue primary sequence of the huifn-gamma, each one with a 7-residue sequence overlap with successive peptide, was synthesized. based on the similar reactivity patterns of all the mabs with this set of synthetic peptides, the e1 functional epitope was loc ...19911706709
novel non-nucleoside inhibitors of hiv-1 reverse transcriptase. 1. tricyclic pyridobenzo- and dipyridodiazepinones.novel pyrido[2,3-b][1,4]benzodiazepinones (i), pyrido[2,3-b][1,5]benzodiazepinones (ii), and dipyrido[3,2-b:2',3'-e][1,4]diazepinones (iii) were found to inhibit human immunodeficiency virus type 1 (hiv-1) reverse transcriptase in vitro at concentrations as low as 35 nm. in all three series, small substituents (e.g., methyl, ethyl, acetyl) are preferred at the lactam nitrogen, whereas slightly larger alkyl moieties (e.g., ethyl, cyclopropyl) are favored at the other (n-11) diazepinone nitrogen. ...19911712395
monoclonal antibody-defined epitope map of expressed rubella virus protein domains.an expanded library of murine monoclonal antibodies (mabs) was generated by infecting balb/c mice with the therien strain of rubella virus (rv) and selecting secreting hybrids by enzyme-linked immunosorbent assay (elisa) using purified virion targets. a panel of plasmids containing specified rv cdna fragments was also constructed by using a variety of strategies with pge374- and pge374-derived expression vectors. hybrid reca-rv-beta-galactosidase (lacz)- or reca-rv-truncated lacz-containing prot ...19911712855
identification of antigenically important domains in the glycoproteins of sindbis virus by analysis of antibody escape variants.to study important epitopes on glycoprotein e2 of sindbis virus, eight variants selected to be singly or multiply resistant to six neutralizing monoclonal antibodies reactive against e2, as well as four revertants which had regained sensitivity to neutralization, were sequenced throughout the e2 region. to study antigenic determinants in glycoprotein e1, four variants selected for resistance to a neutralizing monoclonal antibody reactive with e1 were sequenced throughout the e2 and e1 regions. a ...19911714515
specific interaction between hpv-16 e1-e4 and cytokeratins results in collapse of the epithelial cell intermediate filament network.the human papillomaviruses (hpv) are associated specifically with epithelial lesions, ranging from benign warts to invasive carcinoma. the virus encodes three late proteins, which are produced only in terminally differentiating keratinocytes, two of which are structural components of the virion. the third, e1-e4, is derived primarily from the e4 open reading frame, which represents a region of maximal divergence between different hpv types. e1-e4 does not seem to be a component of the virus part ...19911715519
use of a lambda gt11 expression library to localize a neutralizing antibody-binding site in glycoprotein e2 of sindbis virus.the sindbis virus envelope contains two species of integral membrane glycoproteins, e1 and e2. these proteins form heterodimers, and three dimeric units assemble to form spikes incorporated into the viral surface which play an important role in the specific attachment of sindbis virus to host cells. to map the neutralization epitopes on the surface of the virus, we constructed a lambda gt11 expression library with cdna inserts 100 to 300 nucleotides long obtained from randomly primed synthesis o ...19911719239
[study of the antigenic structure of the e1 glycoprotein of the venezuelan equine encephalomyelitis virus using monoclonal antibodies].the collection of eight rat and mouse hybridomas secreting the high affinity monoclonal antibodies to glycoprotein e1 of the venezuelan equine encephalomyelitis has been obtained. the antigenic structure of e1 protein has been studied with the use of these antibodies for the strains trinidad, tc-83 and 230 of the virus. antigenic map of glycoprotein e1 based on competition radioimmunoanalysis is proposed. five sites are mapped including eight epitopes binding monoclonal antibodies. antibodies to ...19911719387
studies on linear epitopes of semliki forest virus in protection studies against lethal challenge virus infection.purified reduced and non-reduced glycoproteins e1 and e2 of semliki forest virus (sfv) were used to investigate the protection potency to prevent clinical disease after lethal virus challenge. in parallel synthetic oligopeptides deduced from conserved regions of the nucleotide sequences coding for the glycoproteins e1 and e2 were included. it could be demonstrated that both reduced and non-reduced glycoprotein preparations induced protection against lethal virus challenge, whereas the oligopepti ...19911719714
investigation of antigenic structure of attenuated and virulent venezuelan equine encephalomyelitis virus by means of monoclonal antibodies.a comparative study of the antigenic structure of virulent strains and attenuated vaccine strains of venezuelan equine encephalomyelitis virus (veev) by means of monoclonal antibodies has made it possible to investigate the antigenic structure of the envelope glycoproteins e1 and e2, and to specify their role in the development of antiviral immunity. on the e1 glycoprotein there are five nonoverlapping antigenic sites consisting of eight epitopes that are recognized by monoclonal antibodies; six ...19911726775
site-directed mutations in sindbis virus e2 glycoprotein's cytoplasmic domain and the 6k protein lead to similar defects in virus assembly and budding.site-directed mutagenesis was used to obtain four mutants with amino acid replacements in the cytoplasmic domain of the e2 glycoprotein and three with replacements in the 6k protein of sindbis virus. all but one of these mutants yielded progeny virus after transfection of chicken embryo fibroblasts with rna prepared by in vitro transcription of the virus cdna; however, even this nonproducer mutant made virus structural proteins in the transfected cells. the other six mutants divided into two gro ...19911647069
a subtype of human papillomavirus 5 (hpv-5b) and its subgenomic segment amplified in a carcinoma: nucleotide sequences and genomic organizations.a subtype of human papillomavirus 5 (hpv-5b) is closely associated with carcinomas in the disease epidermodysplasia verruciformis (ev). the complete genome was cloned from virus particles in benign lesions of a patient with ev and sequenced: it was 7779 nucleotides long and consisted of six open reading frames (orfs) (e6, e7, e1, e2, e4, and e5) in the early region, three orfs (l2, l3, and l1) in the late region, and a noncoding region, all existing on one dna strand. the 40% segment of the hpv- ...19911649510
antigenic analysis of feline coronaviruses with monoclonal antibodies (mabs): preparation of mabs which discriminate between fipv strain 79-1146 and fecv strain 79-1683.we prepared 31 monoclonal antibodies (mabs) against either fipv strain 79-1146 or fecv strain 79-1683, and tested them for reactivity with various coronaviruses by indirect fluorescent antibody assay (ifa). sixteen mabs which reacted with all of the 11 strains of feline coronaviruses, also reacted with canine coronavirus (ccv) and transmissible gastroenteritis virus (tgev). in many of them, the polypeptide specificity was the recognition of transmembrane (e1) protein of the virus. we succeeded i ...19911653482
a golgi retention signal in a membrane-spanning domain of coronavirus e1 protein.the e1 glycoprotein from an avian coronavirus is a model protein for studying retention in the golgi complex. in animal cells expressing the protein from cdna, the e1 protein is targeted to cis golgi cisternae (machamer, c. e., s. a. mentone, j. k. rose, and m. g. farquhar. 1990. proc. natl. acad. sci. usa. 87:6944-6948). we show that the first of the three membrane-spanning domains of the e1 protein can retain two different plasma membrane proteins in the golgi region of transfected cells. both ...19911655802
activation of bpv-1 replication in vitro by the transcription factor e2.soluble extracts from uninfected murine cells supplemented with purified viral e1 and e2 proteins support the replication of exogenously added papilloma virus dna. the e2 transactivator stimulates the binding of the e1 replication protein to the minimal origin of replication and activates dna replication. these results support the concept that transcription factors have a direct role in the initiation of dna replication in eukaryotes by participating in the assembly of a complex at the origin of ...19911656277
intranuclear distribution of epstein-barr virus-encoded nuclear antigens ebna-1, -2, -3 and -5.epstein-barr virus (ebv)-transformed lymphoblastoid cell lines (lcls) express at least seven virally encoded proteins. their functional role, and their relationships to each other and to normal nuclear constituents are virtually unknown. as the first step towards a topographical study, the intranuclear distribution of ebv-encoded nuclear antigens ebna-1, -2, -3 and -5 (abbreviated e1, e2 etc.) was examined in ebv-transformed lcls by immunofluorescence and digital image analysis of fluorescence p ...19911658016
genomic structure of the human prototype strain h of hepatitis c virus: comparison with american and japanese isolates.genomic rna from the human prototype strain h of the hepatitis c virus (hcv-h) has been molecularly cloned and sequenced. the hcv-h sequence reported consists of 9416 nucleotides including the 5' and 3' untranslated regions. hcv-h shows 96% amino acid identity with the american isolate hcv-1 but only 84.9% with the japanese isolates hcv-j and hcv-bk. in addition to the hypervariable region (region v) previously identified in the putative e2 domain, three other variable domains were identified: r ...19911658800
induction of nad(p)h:quinone reductase in human peripheral blood lymphocytes.the induction of quinone reductase [qr; nad(p)h:(quinone acceptor) oxidoreductase; ec 1.6.99.2] in cultured cells and animal tissues of rodents has provided useful information on mechanisms of protection against carcinogens. we have developed a simple and efficient microtiter plate assay for the direct measurement of qr basal activity and inducibility in human peripheral blood lymphocytes (unstimulated, mitogen-stimulated and epstein-barr virus-transformed) grown in suspension culture. in these ...19911660793
sequence analysis of the putative structural genes of hepatitis c virus from japanese and european origin.cdna fragments encoding the putative structural genes of the hepatitis c genome were isolated from a plasma pool of japanese non-a, non-b hepatitis patients and from sera of individual spanish patients. from the japanese plasma pool a series of e1 clones was obtained that showed 88-98% homology among each other, both at the nucleotide and amino acid level. compared to the sequences published by the chiron corporation and takeuchi et al., the amino acid homology was 75-79% and 91-94%, respectivel ...19911668328
hepatitis c virus (hcv)-rna in non-a, non-b chronic hepatitis in france. nucleotide sequence of a french hcv isolate.the sera of 36 french patients with post-transfusional and sporadic non-a, non-b (nanb) chronic hepatitis were investigated, with a combination of serological and polymerase chain reaction (pcr) assays, for hbv and hcv infections. eighty-nine percent of the patients were found positive with serological and/or molecular tests. among the positive patients, 68% (22/32) were found positive for both anti-hcv and hcv-rna, 16% (5/32) and 16% (5/32) were found positive only for anti-hcv or hcv-rna, resp ...19911668329
efficient in vitro translation and processing of the rubella virus structural proteins in the presence of microsomes.in the structural protein open reading frame (sp-orf) of rubella virus (rub), the sequences for the three virion proteins occur in the order nh2-c-e2-e1-cooh with hydrophobic, consensus signal sequences preceding the amino termini for each of the two membrane proteins (t. k. frey and l. d. marr, 1988 gene 62, 85-100). in vitro translation in the presence of microsomes of rna transcripts from a plasmid containing the sp-orf resulted in production and accurate processing of the three structural pr ...19911984659
internally located cleavable signal sequences direct the formation of semliki forest virus membrane proteins from a polyprotein precursor.the proteolytic processes involved in the cotranslational production of the semliki forest virus proteins p62, 6k, and e1 from a common precursor polypeptide were analyzed by an in vitro translation-translocation assay. by studying the behavior of wild-type and mutant variants of the polyprotein, we show that the signal sequences responsible for membrane translocation of the 6k and e1 proteins reside in the c-terminal regions of p62 and 6k, respectively. we present evidence suggesting that the p ...19911985194
defective transport of sindbis virus glycoproteins in end4 mutant chinese hamster ovary cells.mutant v.24.1, a temperature-sensitive derivative of chinese hamster ovary cells, defines the end4 complementation group of mutants selected for resistance to protein toxins and has defective lysosomes at the restrictive temperature (p. a. colbaugh, m. stookey, and r. k. draper, j. cell biol. 108:2211-2219, 1989). we have investigated the biosynthesis of sindbis virus envelope glycoproteins in v.24.1 cells. when the cells were infected at the restrictive temperature, the envelope glycoproteins e ...19911995947
mechanism of altered sindbis virus neurovirulence associated with a single-amino-acid change in the e2 glycoprotein.the mechanism by which amino acid changes in the e1 and e2 surface glycoproteins of sindbis virus affect neurovirulence is unknown. we have studied two recombinant viruses which differ in virulence. one (te) contains gly and the other (tes) contains arg at position 172 in e2. te causes more rapid death than tes in newborn mice. both viruses replicate similarly in nonneuronal cells, but te replicates more rapidly in the brains of newborn mice and in neuroblastoma cells. te also induces earlier vi ...19911995953
processing of the p62 envelope precursor protein of semliki forest virus.the spike protein of semliki forest virus is composed of three subunits, e1, e2, and e3, which mediate the fusion of the virus membrane with that of the host cell. e2 and e3 are synthesized as a precursor, p62, which is cleaved post-translationally after an arg-his-arg-arg sequence. in vitro mutagenesis of a cdna clone of the spike proteins was used to specifically alter amino acids in this cleavage site. cleavage of p62 was completely blocked by mutation of the proximal arg residue to phe, with ...19912005112
analysis of rubella virus e1 glycosylation mutants expressed in cos cells.cdna clones encoding the envelope glycoprotein e1 of rubella virus (rv) were altered by site-directed mutagenesis at consensus sites for addition of n-linked glycans. the resulting plasmids were introduced into cos cells and the mutant e1 proteins were analyzed by indirect immunofluorescence, radioimmunoprecipitation, and immunoblotting. we found that rv e1 contains three n-linked oligosaccharides, each approximately 2 kda in size. although lack of glycosylation did not appear to affect targetin ...19912014650
characterization of carbohydrates linked to rubella virus glycoprotein e2.rubella virus contains two envelope glycoproteins, e1 and e2. the amino acid sequence for both glycoproteins is known, as is the number of n-glycosylation sites. this study has demonstrated the presence of o-linked carbohydrates bound to e2 and determined structural characteristics of the n-linked oligosaccharide chains. o-linked sugars were found to be resistant to digestion with n-glycanase but sensitive to beta-elimination with alkaline borohydride. after treatment with neuraminidase, o-linke ...19912016596
the influence of capsid protein cleavage on the processing of e2 and e1 glycoproteins of rubella virus.the structural polyprotein of rubella virus is cotranslationally processed by host cell signal peptidase. oligonucleotide-directed mutagenesis was used to alter the cleavage site between capsid and e2 proteins and to examine the importance of this cleavage for the transport and processing of e2 and e1 glycoproteins. the in vitro and in vivo expression of the cleavage site mutant revealed that the e2 polypeptide can cross the endoplasmic reticulum membrane without the cleavage of its signal pepti ...19912053296
detection of rubella virus gene sequences by enzymatic amplification and direct sequencing of amplified dna.we developed a rapid and sensitive polymerase chain reaction (pcr) assay for detecting and identifying rubella virus (rv). a segment of the rv gene which encodes the e1 membrane glycoprotein of rv was selected as a target for pcr amplification. single-stranded viral rna, extracted from infected cells or released from virions, was used as a template for reverse transcription followed by pcr amplification with two different sets of primer pairs, one nested within the other. the amplified e1 gene s ...19912056062
in vitro mutagenesis of a full-length cdna clone of semliki forest virus: the small 6,000-molecular-weight membrane protein modulates virus release.we report on the construction of a full-length cdna clone of semliki forest virus (sfv). by placing the cdna under the sp6 promoter, infectious rna can be produced in vitro and used to transfect cells to initiate virus infection. to achieve efficient transfections, a new protocol for electroporation of rna was developed. this method gave up to 500-fold improvement over the traditional deae-dextran transfection procedure. since virtually 100% of the cells can be transfected by electroporation, th ...19912072446
mutagenesis of the putative fusion domain of the semliki forest virus spike protein.semliki forest virus (sfv), an alphavirus, infects cells via a low ph-triggered membrane fusion reaction that takes place within the cellular endocytic pathway. fusion is mediated by the heterotrimeric virus spike protein, which undergoes conformational changes upon exposure to low ph. the sfv e1 spike subunit contains a hydrophobic domain of 23 amino acids that is highly conserved among alphaviruses. this region is also homologous to a domain of the rotavirus outer capsid protein vp4. mutagenes ...19912072453
diagnostic potential of baculovirus-expressed rubella virus envelope proteins.the envelope glycoproteins e1 and e2 of rubella virus were abundantly expressed in spodoptera frugiperda sf9 insect cells by using a baculovirus expression vector. the recombinant protein products were purified by immunoaffinity chromatography and characterized by sodium dodecyl sulfate-polyacrylamide gel electrophoresis, immunoblotting, and enzyme immunoassay (eia). the purified recombinant antigen consisted of the envelope polypeptides, corresponding to the viral e1 and e2 proteins, and a poly ...19911774311
recombinant baculoviruses expressing yellow fever virus e and ns1 proteins elicit protective immunity in mice.recently, we showed that yellow fever virus (yfv) e and ns1 proteins in spodoptera frugiperda cells infected with a recombinant baculovirus are similar, if not identical to those produced during yfv infection. to study the role of e and ns1 in the induction of protective immunity against fatal yfv challenge, these viral antigens were expressed either alone or in tandem via recombinant baculoviruses ac-e. ns1, ac-e1 and ac-ns1. swiss mice were immunized with lysates of insect cells infected with ...19911834798
variable and hypervariable domains are found in the regions of hcv corresponding to the flavivirus envelope and ns1 proteins and the pestivirus envelope glycoproteins.based on the flavi- and pestivirus model of genome organization for the hepatitis c virus (hcv) (1-5), the nucleotide and deduced amino acid sequences of the putative envelope (e1) and the junction between the e1 and ns1/envelope 2 (e2) region from six different human isolates of hcv were compared with the nucleotide and predicted amino acid sequences of the prototype hepatitis c virus (hcv-1) (5). the overall percentage of nucleotide and amino acid changes among all six isolates, including hcv- ...19911846505
detection of alphaviruses in a genus-specific antigen capture enzyme immunoassay using monoclonal antibodies.a genus-specific antigen capture assay using similar combinations of monoclonal antibodies for capture and detection of 24 alphaviruses belonging to the seven serocomplexes was developed. the sensitivity of the test ranged from 10(3.4) 50% tissue culture infective doses/ml for o'nyong-nyong virus to 10(6.1) 50% tissue culture infective doses/ml for middelburg virus. the antigen capture test uses a combination of cross-reacting monoclonal antibodies directed against the nucleocapsid protein and e ...19911847149
protein-protein interactions in an alphavirus membrane.using homobifunctional chemical cross-linkers with various span distances, we have determined the near-neighbor associations and planar organization of the e1 and e2 envelope glycoproteins which compose the icosahedral surface of sindbis virus. we have found that e1-e2 heterodimers, which form the virus protomeric units, exist in two conformationally distinct forms, reflecting their nonequivalent positions in the icosahedron. three of these heterodimers form the trimeric morphologic units (capso ...19911847448
proteolytic processing of the sindbis virus membrane protein precursor pe2 is nonessential for growth in vertebrate cells but is required for efficient growth in invertebrate cells.we have shown previously that processing of the sindbis virus envelope protein precursor pe2 to envelope protein e2 is not required for virus maturation in cultured vertebrate fibroblast cells and that unprocessed pe2 can be incorporated into infectious virus in place of e2 (j. f. presley and d. t. brown, j. virol. 63:1975-1980, 1989; d. l. russell, j. m. dalrymple, and r. e. johnston, j. virol. 63:1619-1629, 1989). to better understand the role of this processing event in the invertebrate vecto ...19911848310
a mutant cho-k1 strain with resistance to pseudomonas exotoxin a and alphaviruses fails to cleave sindbis virus glycoprotein pe2.rpe.40, a mutant cho-k1 strain selected for resistance to pseudomonas exotoxin a, is defective in the production of infectious alphaviruses, although viruses are taken in and processed normally (j. m. moehring and t. j. moehring, infect. immun. 41:998-1009, 1983). to determine the cause of this defect, the synthesis of sindbis virus proteins was examined. rpe.40 cells produced and glycosylated structural glycoprotein precursors pe2 and immature e1 normally. mature e1 was formed, but pe2 was not ...19911850015
live attenuated pseudorabies virus expressing envelope glycoprotein e1 of hog cholera virus protects swine against both pseudorabies and hog cholera.to investigate whether live attenuated pseudorabies virus (prv) can be used as a vaccine vector, prv recombinants that expressed envelope glycoprotein e1 of hog cholera virus (hcv) were generated. pigs inoculated with these recombinants developed high levels of neutralizing antibodies against prv and hcv and were protected against both pseudorabies and hog cholera (classical swine fever).19911850051
multiple sets of adjacent mu e1 and oct-1 binding sites upstream of the pseudorabies virus immediate-early gene promoter.binding of cellular proteins to specific motifs in the promoter region of the immediate-early gene of pseudorabies virus was studied. the region was dissected into several portions that were used with hela cell nuclear proteins in mobility shift assays, dnase i footprinting, and a methylation interference assay. close to the transcription start site (nucleotide + 1) are a tata-box (-26 to -29), an sp 1-binding motif (ggggcgggc) (-45 to -54), a ccaat motif (-66 to -70), and, further upstream, an ...19911850904
characterization of bovine papillomavirus e1 region deletion mutants associated with neoplastic transformation in a murine cell line.spontaneous focus formation in the contact-inhibited c127 cell line, cl.2, harbouring multiple copies of a bovine papillomavirus type 1 deletion mutant, was associated with the evolution of further viral genomic deletions in addition to an amplification of the viral genome copy number. three simple frameshift deletions of 308, 605 and 1291 bp, associated with separate transformation events, were mapped within the e1 open reading frame, implying a common mechanism of spontaneous transformation in ...19911851818
vaccinia-vectored expression of the rubella virus structural proteins and characterization of the e1 and e2 glycosidic linkages.the maturation of rubella virus (rv) glycoprotein e2 from the single intracellular species (e2i; mw = 40 kda) to the heterodisperse virion species (e2v; mw = 42 to 47 kda), was studied by pulse-chase radiolabeling in vero cells infected with rv or with recombinant vaccinia viruses (vvs) which express the entire rv structural protein open reading frame (vv-ce2e1) or glycoprotein e2 independently (vv-e2). the rv proteins expressed by the recombinant vvs comigrated with authentic rv intracellular p ...19911853566
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