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cloning of adenovirus type 12 e1 genes into a retroviral vector and their differential splicing in mouse cells.early region 1 (e1) of adenovirus type 12 (ad12) genome is able to transform nonpermissive primary rodent cells in vivo and in vitro. to analyse the role of the e1a gene products alone or in connection with the 58-kda protein encoded by e1b during oncogenic transformation, we have cloned genomic fragments of both subregions into the retroviral vector, pzip-neosv(x)1. both constructs are expressed in mouse 3t3 cells, but, in contrast to e1b, the amount of genomic retroviral rna carrying e1a-speci ...19902145196
differential requirement for adenovirus type 12 e1a gene products in oncogenic transformation.during the early period of infection, adenovirus type 12 e1a gene is expressed as overlapping, spliced mrnas of 12 and 13s, which encode in-frame proteins of 235 and 266 amino acid residues (235r and 266r), respectively. to define the functions of these related products in the infection of human cells and transformation of rodent cells, we created single t-to-c transitions at the second base of each mrna intron which specifically prevent splicing of the respective mrnas. mutant pm712 expresses o ...19902144595
induction of gd3 ganglioside by adenovirus e1a gene 13s- and 12s-mrna products in rat 3y1 cells.the effect of the expression of the human adenovirus type 12 e1a gene on ganglioside composition of rat 3y1 cells was investigated using cell lines established by introduction of recombinant vector dna containing the e1a 13s- or 12s-mrna cdna placed downstream of the hormone-inducible promoter of mouse mammary tumor virus. ganglioside gd3 was newly detected after switching on of either 13s- or 12s-mrna cdna by addition of dexamethasone. a kinetic study indicated that gd3 was expressed 8 h after ...19902144522
adenovirus type 12 tumour antigen synthesis differs during infection of permissive and non-permissive cells.synthesis of the adenovirus type 12 e1a and e1b tumour antigens was compared in productively infected human (kb) cells and in abortively infected baby hamster kidney (bhk) cells. by the use of anti-peptide antibodies, the e1a tumour antigens were easily detectable in infected kb extracts as early as 6 h post-infection, but were not detectable in infected bhk extracts until 12 h post-infection. the level of e1a tumour antigens detected in bhk extracts was 10 to 15% of that detected in kb extracts ...19902138209
identification of sequences responsible for positive and negative regulation by e1a in the promoter of h-2kbm1 class i mhc gene.the mechanism of transcriptional regulation of the h-2kbm1 major histocompatibility complex (mhc) class i gene by adenovirus type 12 e1a (ad12-e1a) was studied in transfected rat embryonal fibroblasts. results of long-term expression of the chloramphenicol acetyl transferase (cat) gene placed under the control of the 5'-flanking region of the mouse mhc class i gene. h-2kbm1, and the results of nuclear run-on transcription assays, yield evidence for both positive and negative regulation of h-2kbm ...19902136829
formation in vitro of the ptp-dcmp initiation complex of human adenovirus type 12.we report the covalent addition of [32p]dcmp to a protein from group a adenovirus 12 (ad12)-infected human (kb) cells in vitro, using crude extracts. synthesis of the 60k protein-dcmp complex required a dna template containing a terminally located adenovirus replication origin; the protein-dcmp bond was alkali-labile but acid-stable. we therefore conclude that this product is the ad12 terminal protein precursor (ptp)-dcmp initiation complex for dna replication. synthesis of ad12 ptp-dcmp was spe ...19911993880
transcriptional and posttranscriptional regulation of class i major histocompatibility complex genes following transformation with human adenoviruses.transformation of rodent cells by human adenoviruses is a well-established model system for studying the expression, regulation, and function of class i antigens. in this report, we demonstrate that the highly oncogenic adenovirus type 12 operates at the transcriptional and posttranscriptional levels in regulating the activity of major histocompatibility complex class i genes and products in transformed cells. adenovirus type 12 suppresses the cell surface expression of class i antigens in most ...19911895404
different chemosensitivities of rat 3y1 fibroblasts transformed by various agents in vitro.alterations of chemosensitivities associated with transformation of rat 3y1 fibroblasts were compared among various agents, including either adenovirus type 12 (ad12-3y1), the e1a region of adenovirus type 12 (e1a-3y1), mouse polyoma virus (py-3y1), simian virus 40 (sv-3y1), rous avian sarcoma virus (sr-3y1), plasmid dna carrying v-ha-ras oncogene (hr-3y1), or n-methyl-n'-nitro-n-nitrosoguanidine (ng-3y1), with untransformed 3y1 fibroblasts, using a semiautomated non-clonogenic mtt assay. ic50 v ...19911888164
suppression of murine leukemia virus-mediated 3y1 cell fusion by expression of mouse mhc class i.rat 3y1 fibroblasts transformed by adenovirus type 12 or its e1a gene formed syncytia by cocultivation with friend murine leukemia virus (mulv)-producing cells. on the other hand, parental 3y1 cells and those derivatives induced by other tumor viruses or chemical carcinogen showed no mulv-mediated syncytium formation [n. momozaki et al. (1990) arch. virol. 115: 123-126]. the expression of major histocompatibility complex (mhc) class i mrna and antigens was significantly reduced in these ad12- an ...19911863224
the use of beta-galactosidase fusion proteins encoding the early region 1 transforming proteins of adenovirus type 12 to examine the humoral response in tumour-bearing animals.sera from 26 rats bearing tumours induced by wild-type (wt) and mutant human adenovirus type 12 (ad12), or by cells transformed with these viruses, were analysed for antibodies against the early region 1 (e1) transforming proteins. six ad12-beta-galactosidase fusion proteins encoding different regions of the ad12 e1 proteins were constructed. the sera from the tumour-bearing animals reacted most strongly with the fusion protein encoding the n terminus of the e1a protein. tumour-bearing rats expo ...19911849978
differential regulation of junb and jund by adenovirus type 5 and 12 e1a proteins.the genes of the jun family encode components of the tpa-inducible transcription factor ap-1. these genes are induced by a wide variety of extracellular stimuli, such as growth factors, phorbol esters and activators of protein kinase a. we have previously shown that the adenovirus type 5 e1a protein (e1a5) induces c-jun and junb expression in a number of different cell types. in this paper we show that the third member of the jun family, jund, is also strongly induced by e1a5. multiple sequences ...19911837351
transcription stimulation of the adenovirus type-12 e1a gene in vitro by a novel factor bound to a region adjacent to a tata box.the e1a gene of adenovirus (ad) type-12 possesses two transcription start points (tsp) separated by 139 nucleotides (nt). we previously found that transcription from a tsp distal to the coding region is preferentially stimulated in a cell-free reaction by nuclear factor i (nf-i) bound to a region near the left end of the virus genome. we report here on the identification of a cis-acting dna region and a trans-acting factor for transcription initiated at the proximal tsp of the ad12 e1a gene. a d ...19911837279
viral transformation increases vitamin k-dependent gamma-carboxylation of glutamate.mammalian cells contain a microsomal vitamin k-dependent carboxylase activity which catalyzes the gamma-carboxylation of glutamate. while most cells have a limited ability to fully gamma-carboxylate proteins, it has been suggested that the ability of transformed cells to perform this complex post-translational modification may play a role in tumor biology. in this study, we examined the effect of transformation by adenovirus oncogenes on the ability of cells to efficiently gamma-carboxylate a vi ...19911824587
genomic dna analysis of rat retinal tumor induced by adenovirus type 12.to elucidate the pathogenesis of human retinoblastoma, we investigated the genomic expression in retinal tumors induced by human adenovirus type 12 in rats, using various dna probes. seven rats received a single intraocular inoculation of concentrated virus fluid within 24 hours after birth. intravitreous tumors were induced in two out of seven animals (28.5%) within 30 to 64 days after the inoculation. a remarkably uniform histologic feature, i.e., neuroblastic cells in association with homer-w ...19911785341
changes in nf-kappa b and isgf3 dna binding activities are responsible for differences in mhc and beta-ifn gene expression in ad5- versus ad12-transformed cells.changes in mhc class i expression are frequently observed in tumors, which represents at least one mechanism by which tumor cells escape immune surveillance. mhc class i expression is often suppressed in type 12 adenovirus (ad12)-transformed rodent cells, but is highly induced in ad5-transformed cells. this difference helps to explain why ad12 but not ad5 can induce tumors in immunocompetent syngeneic rats. in this report we demonstrate that only ad5- but not ad12-transformed rodent fibroblasts ...19911756724
identification of reactive synthetic gliadin peptides specific for coeliac disease.gluten intolerance (coeliac disease) is characterised by the development of a small intestinal lesion following exposure to the gliadin fraction after consumption of wheat and related cereals. cellular immune mechanisms are thought to be responsible for gliadin toxicity, but the toxic sequence/s within gliadin have not been clearly established. a panel of synthetic gliadin peptides was tested using peripheral blood mononuclear cells from coeliac patients and two assays for cell-mediated immunity ...19911720424
spreading of dna methylation across integrated foreign (adenovirus type 12) genomes in mammalian cells.the establishment of de novo-generated patterns of dna methylation is characterized by the gradual spreading of dna methylation (i. kuhlmann and w. doerfler, j. virol. 47:631-636, 1983; m. toth, u. lichtenberg, and w. doerfler, proc. natl. acad. sci. usa 86:3728-3732, 1989; m. toth, u. müller, and w. doerfler j. mol. biol. 214:673-683, 1990). we have used integrated adenovirus type 12 (ad12) genomes in hamster tumor cells as a model system to study the mechanism of de novo dna methylation. ad12 ...19911712860
cellular hypersensitivity to a synthetic dodecapeptide derived from human adenovirus 12 which resembles a sequence of a-gliadin in patients with coeliac disease.the human intestinal adenovirus serotype 12 (ad12) may be implicated in the pathogenesis of coeliac disease by virtue of immunological cross reactivity between epitopes shared by its early region e1b protein and a-gliadin. in the present study a synthetic dodecapeptide from the corresponding viral epitope (ad12e1b, residues 384-395) was tested for its effect on peripheral blood mononuclear cells from 22 treated and eight untreated patients with coeliac disease, 22 healthy subjects, 11 patients w ...19901696236
synergism between aphidicolin and adenoviruses in the induction of breaks at fragile sites on human chromosomes.infection of human embryonic kidney cells with adenoviruses results in the induction of gaps and breaks in cell chromosomes. with adenovirus type 12, cytogenetic damage is known to occur primarily at fragile sites on chromosomes 1 and 17. we have mapped adenovirus type 5-induced breaks and have observed that, although they occur on all chromosomes, they are localized primarily on bands where fragile sites have been mapped. the susceptibility of fragile sites to adenovirus led us to investigate t ...19911648440
acceleration of adenovirus replication and increased virion production by treatment with the steroid hormone 17 beta-estradiol.we report here that concentration of an estrogen known to promote enhanced transformation and to increase oncogenicity of rat embryo cells, accelerate the production and increase the yield of progeny virions in adenovirus type 12 (ad 12)-infected hep-2 cells. further, measurement of the incorporation of radioactive rna and dna precursors indicated that macromolecular synthesis in the estrogen-treated, infected cells was accelerated. possible explanations for this observation are discussed.19921584077
altered expression of adenovirus 12 dna-binding protein but not dna polymerase during abortive infection of hamster cells.replication of human adenovirus type 12 dna is blocked in abortively infected baby hamster kidney cells. the activity and accumulation of adenovirus 12 dna polymerase is equivalent in infected hamster and human cell extracts. however, the accumulation of adenovirus type 12 dna-binding protein is approximately 120-fold lower in extracts from infected hamster cells when compared to infected permissive human cells. this difference in accumulation is not due to replication of viral dna during produc ...19921534951
recombinant human adenoviruses containing hybrid adenovirus type 5 (ad5)/ad12 e1a genes: characterization of hybrid e1a proteins and analysis of transforming activity and host range.hybrid adenovirus type 12 (ad12)/ad5 e1a genes were constructed by homologous recombination in escherichia coli, a technique which offers several advantages over conventional mutagenesis for genetic analysis of proteins. in particular, functional differences between the proteins can be mapped by correlating the replacement of specific sequences with the acquisition of new properties, and there is no requirement for common unique restriction sites or polymerase chain reaction strategies to constr ...19921534849
activation of the mouse dna polymerase beta gene promoter by adenovirus type 12 e1a proteins.a plasmid carrying the 5'-flanking region (-1852 to +33 with respect to the transcription initiation site) of the mouse dna polymerase beta gene fused with the chloramphenicol acetyltransferase (cat) gene was cotransfected into mouse n18tg2 cells with adenovirus type 12 e1 genes-expressing plasmids. expression of e1a gene products resulted in the elevation of the cat expression by 3 to 7 folds, but that of e1b gene product was much less effective. rnase protection analysis revealed that the acti ...19921534405
overexpression of the e1b 55-kilodalton (482r) protein of human adenovirus type 12 appears to permit efficient transformation of primary baby rat kidney cells in the absence of the e1b 19-kilodalton protein.to analyze the structure and function of the e1b 19,000-molecular-weight protein (19k protein) (163r) of human adenovirus type 12, mutants were produced at various positions across the 163r-coding sequence. viruses bearing mutations within the first 100 or so amino acids yielded unstable 163r-related products, induced dna degradation and enhanced cytopathic effect (cyt/deg phenotype) in kb cells, and transformed primary rodent cells at much lower efficiencies than wild-type (wt) virus. deletion ...19921532214
recombination between adenovirus type 12 dna and a hamster preinsertion sequence in a cell-free system. patch homologies and fractionation of nuclear extracts. 19921474593
adenovirus type 12 early region 1b proteins and metabolism of early viral mrnas.early region 1b (e1b) of human adenoviruses encodes two major proteins. the 19-kda polypeptide appears to prevent e1a-induced cytolysis and dna degradation. the larger e1b product of approximately 55 kda, which is essential for viral replication, plays a role in the accumulation and stability of viral mrnas and the late shutoff of host metabolism. for serotype 12 (ad12), this 482-residue (482r) protein is essential for viral dna replication. in the present report we have used a series of mutants ...19921448923
alterations in the levels of expression of specific cellular genes in adenovirus-infected and -transformed cells.there is increasing evidence that changes in the transcriptional program of cellular genes in virus-transformed cells can contribute to virus transformation. it is, therefore, important to study altered expression patterns of cellular genes in adenovirus-infected and -transformed cells. we have used 40 different cellular genes or gene segments as hybridization probes to analyze the cytoplasmic rna from adenovirus type 2 (ad2)-infected kb cells, from ad5-transformed human cells (293) or from seve ...19921441738
negative regulation of the major histocompatibility complex class i enhancer in adenovirus type 12-transformed cells via a retinoic acid response element.in cells transformed by the highly oncogenic adenovirus type 12 (ad12), the viral e1a proteins mediate transcriptional repression of the major histocompatibility class i genes. in contrast, class i transcription is not reduced in cells transformed by the nononcogenic ad5. the decreased rate of class i transcription is, at least in part, the result of a reduced major histocompatibility complex class i enhancer activity in ad12-transformed cells and correlates with an increase in the levels of a d ...19921433503
down-regulation of the major histocompatibility complex class i enhancer in adenovirus type 12-transformed cells is accompanied by an increase in factor binding.in transformed cells, the e1a gene of adenovirus type 12 (ad12) represses transcription of class i genes of the major histocompatibility complex. the tumorigenic potential of ad12-transformed cells correlates with this diminished class i expression. in contrast, the e1a gene of the nontumorigenic ad5 does not affect class i expression. we show here that a transfected reporter chloramphenicol acetyltransferase plasmid driven by an h-2k promoter (-1049 bp) was expressed at much lower levels in ad1 ...19921433502
reduced binding activity of transcription factor nf-kappa b accounts for mhc class i repression in adenovirus type 12 e 1-transformed cells.the early region 1 (e1) of human adenovirus (ad) type 12 represses the expression of major histocompatibility (mhc) class i genes in transformed primary rodent cells. in this paper we show that both nf-kappa b and kbf1 (p50 dimer) binding activity to the h2tf1 element in the class i promoter is reduced in ad12-13s-e1a-transformed cells compared to ad5e1- or ad12-12s-e1a-transformed cells. consistently, in ad12e1a-13s-transformed cells the h2tf1 element does not contribute to transcriptional acti ...19921423646
production of a low molecular weight growth inhibitory factor by adenovirus 12-transformed cells.malignant rodent cells transformed by human adenovirus 12 produce a potent cell growth inhibitory factor. the cell growth inhibitory factor inhibits the growth of and dna synthesis in normal fibroblasts in vitro. extent of the production of the cell growth inhibitory factor appears to be proportional to that of the malignancy of the transformed cells. c57at1-ab cells, an adenovirus 12-transformant of c57bl/6 mouse origin, are highly tumorigenic in the syngeneic and allogeneic mice. the cell grow ...19921417799
molecular cloning of cdna encoding a human heat-shock protein whose expression is induced by adenovirus type 12 e1a in hela cells.we have identified by differential plaque hybridization, human cdna clones encoding a member of a heat-shock protein family (hsp 90 alpha) in the cdna library of adenovirus type 12 e1a transfected hela cells. the complete nucleotide sequence of one of the clones (phb76-114a) was identified. the sequence of 2912 base pairs had a single reading frame with a coding potential for an 84,672-da protein. the amino acid sequence was highly homologous, but not identical, to that of the human hsp 90 alpha ...19901368637
activation of the mouse proliferating cell nuclear antigen gene promoter by adenovirus type 12 e1a proteins.a plasmid carrying the 5'-flanking region (-1584 to +47 with respect to the transcription initiation site) of the mouse proliferating cell nuclear antigen (pcna) gene was fused with the chloramphenicol acetyltransferase (cat) gene, and then cotransfected into mouse n18tg2 cells with expression plasmids for the adenovirus type 12 e1 genes. expression of e1a gene products elevated the cat expression by 5- to 9-fold, but expression of the e1b gene product did not. rnase protection analysis revealed ...19921353754
restriction endonuclease patterns of adenovirus type 12 and 18.restriction endonuclease analysis using 10 restriction enzymes was performed on six and three wild isolates of adenovirus (ad) type 12 and 18, respectively. among the ad12 strains, five dna variants could be identified. the degree of pairwise comigration of restriction fragments suggests a high degree of genomic diversity within ad12. the wild isolates of ad18, on the other hand, displayed a low degree of genetic variability and comprised one dna variant closely related to the prototype strain. ...19921331143
adenovirus e1a proteins stimulate inositol phospholipid metabolism in pc12 cells.to study the influence of nuclear oncogenes on inositol phospholipid metabolism, we examined the various parameters of inositol phospholipid metabolism in pc12 cells expressing adenovirus type 12 or adenovirus type 5 e1a. although the inositol 1,4,5-trisphosphate content was increased only slightly, the diacylglycerol content was 2.4-fold higher in e1a-expressing pc12 cells. furthermore, we found that the activity of phospholipase c, one of the key enzymes in inositol phospholipid metabolism, wa ...19921326659
recombination between adenovirus type 12 dna and a hamster preinsertion sequence in a cell-free system. patch homologies and fractionation of nuclear extracts.we have previously described a cell-free recombination system derived from hamster cell nuclear extracts in which the in vitro recombination between a hamster preinsertion sequence, the cloned 1768 base-pair p7 fragment, and adenovirus type 12 (ad12) dna has been demonstrated. the nuclear extracts have now been subfractionated by gel filtration on a sephacryl s-300 column. the activity promoting cell-free recombination elutes from the sephacryl s-300 matrix with the shoulder and not the peak fra ...19921320127
establishment and characterization of cell lines from human adenovirus type 12-induced murine tumors producing endogenous virus particles.two cell lines designated ic-kms and d-kms were established from human adenovirus type 12-induced tumors of c3hf/ok mouse. the cell lines retained the characteristics of the original tumor i.e., production of numerous c-type and intracisternal a-type particles, integration of ad12 e1 region dna and amplification of the myc gene family. chromosomal analysis revealed chromosome aberrations in both ic-kms and d-kms cells. the modal chromosome number of ic-kms cells was 54 and that of d-kms cells wa ...19921319100
driving adenovirus type 12-transformed balb/c mouse cells to express high levels of class i major histocompatibility complex proteins enhances, rather than abrogates, their tumorigenicity.the tumorigenicity of adenovirus type 12 (ad12)-transformed cells has been attributed to the low levels of class i major histocompatibility complex (mhc) protein expression by these cells. these levels of class i proteins are thought to be below the threshold critical for cytotoxic t-lymphocyte recognition, a process that may be involved in tumor cell immunosurveillance. we have used gene transfer experiments to investigate the role played by class i protein expression in the tumorigenicity of a ...19921313906
highly efficient focus formation by rous sarcoma virus on adenovirus type 12 e1a-transformed rat 3y1 cells.when rat 3y1 cells were infected with rous sarcoma virus (rsv) variant sr-rsv-d(h), many 3y1 cells acquired a stable provirus but only few of them formed transformed foci. in contrast, 12e1ay cells (3y1 cells expressing the adenovirus type 12 [ad12] e1a protein) formed transformed foci upon rsv infection with the same high frequency as did chicken embryo fibroblast cells. this enhancement of focus-forming efficiency was specifically observed in 3y1 cells expressing ad12 e1a protein but was not o ...19921310757
chromosome alterations contribute to neoplastic progression of transformed rat embryonal fibroblasts.three types of transformants derived from rat embryonal fibroblasts (refs) corresponding to the different progressional stages were obtained: tf1 (human papillomavirus type 16 e7 (hpv16 e7) transfection alone) and tf2 (e7 plus adenovirus type 12(ad12) e1b were immortalized, tf3 (e7 plus adenovirus type 5 (ad5) e1b) was anchorage-independent but not tumorigenic, and tf4 (e7 plus ej-ras) was tumorigenic. cytogenetic investigations revealed that the cells carrying specific chromosomal abnormalities ...19921309485
evidence for post-transcriptional selection of viral mrna in cells transformed by human adenovirus 12. 19761272415
double-stranded dna binding of adenovirus type 12 tumor antigen. 19761253982
temperature-sensitive mutants of type 12 adenovirus defective in a late function: protein synthesis and evidence for recombination between mutants in complementation group d.four temperature sensitive mutants of adenovirus type 12, classified into complementation group d, synthesize most or all of the late virus-specific polypeptides at the restrictive temperature, as shown by sodium dodecyl sulphate-polyacrylamide gel electrophoresis. infections by these mutants under restrictive conditions apparently result in some over production of the virion hexon polypeptide compared to wild type infection. genetic recombination between the four mutants has been demonstrated. ...19761245844
[isoenzymes of lactate and malate dehydrogenases in nuclei of rat embryo fibroblasts infected with oncogenic adenovirus type 12].the isoenzymatic spectrum of lactatedehydrogenase (ldg; l-lactate: nad-oxireductase; ec 1.1.1.27) and malatedehydrogenase (mdg; 1-malate: nad-oxireductase; ec 1.1.1.37) in nuclei of rat embryo fibroblast cells infected with adenovirus type 12 was studied at 3, 5, 8, 18 and 24 days of cultivation. the nuclei were isolated according to the method of showo et al. modified by zbarsky and georgiev. proteins were fractionated by disc electrophoresis in polyacrylamide gel. in the course of oncovirus-ce ...19751241176
gene functions of adenovirus type 12: synthesis of nuclear acidic proteins in human embryo kidney cells. 19751208875
replication of human kb cell dna after infection by adenovirus type 12. 19751207745
[detection of adenovirus type-12 in sarcomas induced by this virus in hamster].cells of transplantable sarcomas primarily induced in hamsters with adenovirus, type 12, produced persistantly this virus in an infective form. in sera of sarcomabearing hamsters virus-neutrolizing antibodies and antibodies to t-antigen of tumors were revealed. the presence of t-antigen in cells of all types of sarcoma a-12 was demonstrated by means of immunofluorescence, as well as the absence of a specific luminescence of surface membranes of a-12 mml sarcoma cells, obtained from pulmonary mic ...19751189365
transcription of the genome of adenovirus type 12. viral mrna in productively infected kb cells.in human kb cells productively infected with adenovirus type 12, viral dna replication starts between 12 and 14h postinfection. virus-specific, polysome-associated mrna was investigated early (6-8h) and late (26-28h) after infection. most of the viral mrna was polyadenylated and accounted for 0.46% and 24.1% of the mrna synthesized early and late postinfection, respectively. the viral-specific mrna isolated both early and late after infection falls into several distinct size-classes, ranging in ...19751183441
virus specific rna in hamster cells abortively infected with human adenovirus type 12. 19751171554
transcription of the genome of adenovirus type 12. i. viral mrna in abortively infected and transformed cells.in baby hamster kidney (bkh-21) cells abortively infected with adenovirus type 12, polysome-associated, virus-specific rna could be detected starting 5 to 7 h after infection. the amount of this rna reached a maximum between 10 to 12 h after infection and continued to be synthesized at a reduced level until late in infection (48 to 50 h.). in bhk-21 cells transformed by adenovirus type 12 (hb cells), 0.26% of the polysome-associated mrna was virus specific. the size of the virus-specific mrna is ...19751167602
isolation and characterization of adenovirus type 12 dna binding proteins. 19751162902
complementation of human adenovirus type 5 ts mutants by human adenovirus type 12.temperature-sensitive mutants of type 5 adenovirus belonging to eight complementation groups were complemented in mixed infection by type 12 adenovirus, whereas mutants of 7 other groups were not enhanced. in some crosses, phenotypic mixing took place. no evidence of recombination between type 5 ts mutants and type 12 was found.19751113379
dna methylation in adenovirus, adenovirus-transformed cells, and host cells.dnas of adenovirus type 2 and type 12 contain low amounts of methylated bases (0.01 and 0.02% n6-methyl-adenine per adenine, if any, and 0.04 and 0.06% 5-methylcytosine per cytosine for type 2 and type 12, respectively), whereas the dna of the mammalian host cells contains much more 5-methylcytosine (3.57% for human kb cells). the dna of hamster cells transformed by adenovirus type 12 contains 3.11 and 3.14% 5-methycytosine (ha12/7 and t627 cells, respectively), whereas the dna from untransforme ...19761069277
freeze-etching observation on the nucleus of hela-s3 cell infected with adenovirus type 12. 19761027897
decreased transforming ability of a temperature-sensitive mutant of human adenovirus type 12.a mutant of human adenovirus type 12, temperature-sensitive for virus replication an for the enhancement of thymidine incorporation in resting human embryonic kidney cells, is described. the mutant was also temperature-sensitive for transformation of rat cells. the results indicate that a viral gene required for the virus growth cycle is also required for transformation.19761016956
inhibition of intracellular multiplication of adenovirus by interaction between infected and uninfected cells.the possibility that virus multiplication may be inhibited by interaction of infected cells with uninfected cells was tested by experiments, using human adenovirus type 12 (ad12). permissive human cells (human embryonic kidney-hek,kb or hela) were infected and seeded on uninfected or infected "nonpermissive" cell (human embryonic lung=hel) monolayers, and virus yields or proportions of viral antigen-synthesizing cells were compared with each other. both the virus yields and the proportions of vi ...1976994351
intracellular forms of adenovirus dna. v. viral dna sequences in hamster cells abortively infected and transformed with human adenovirus type 12.the persistence of viral dna in bhk-21 cells abortively infected with human adenovirus type 12 has been investigated using reassociation kinetics. no indication of an increase in the amount of viral dna per cell has been found. on the contrary, the amount of intracellular viral dna sequences decreases rapidly after infection. thus, free adenovirus type 12 dna does not replicate in bhk-21 cells. the influence of the multiplicity of infection on the amount of persisting adenovirus type 12 dna has ...1976988194
transcription of the genome of adenovirus type 12. iii. maps of stable rna from productively infected human cells and abortively infected and transformed hamster cells.the adenovirus type 12-specific mrna and the stable nuclear rna from productively infected kb cells, early postinfection, from abortively infected bhk-21 cells, and from the adenovirus type 12-transformed hamster lines t637 and ha12/7 have been mapped on the genome of adenovirus type 12. the intact separated heavy (h) and light (l) strands of adenovirus type 12 dna have been used to determine the extent of complementarity of the mrna or nuclear rna from different cell lines to each of the strand ...1976988193
synthesis of va rna in productive and abortive infections with adenovirus type 12. 1976982836
adenovirus type 12-specific rna sequences during productive infection of kb cells.the complementary strands of adenovirus type 12 dna were separated, and virus-specific rna was analyzed by saturation hybridization in solution. late during infection whole cell rna hybridized to 75% of the light (1) strand and 15% of the heavy (h) strand, whereas cytoplasmic rna hybridized to 65% of the 1 strand and 15% of the h strand. late nuclear rna hybridized to about 90% of the 1 strand and at least 36% of the h strand. double-stranded rna was isolated from infected cells late after infec ...1976950688
a unique pattern of integrated viral genes in hamster cells transformed by highly oncogenic human adenovirus 12.we have analyzed the viral dna sequences persisting in he c19, a clonal line of hamster embryo cells transformed in vitro by human adenovirus 12 (ad 12), a member of highly oncogenic group a. saturation-hybridization of in vitro labeled ad 12 dna (2-4 x 10(8) cpm/mug) with he c19 dna showed that 93-100% of viral dna sequences are present in the transformed cell. reassociation of ad 12 32p-dna in the presence of he c19 dna detected 8 viral genome equivalents per diploid quantity of cell dna. rean ...1976947550
solubilization and purification of surface antigen of cells transformed by adenovirus type 12. 1976944966
[changes in the isoenzymatic spectrum of energy metabolism enzymes and in the mitochondrial ultrastructure in viral carcinogenesis].the dynamics of redistribution of the isoenzymatic spectrum of lactate and malate dehydrogenases in the cells of rat embryo fibroblasts (ref) having been in contact with human adenovirus type 12, as compared to the dynamics of changes in the fine structure of the cellular mitochondria of the same models was studied. the action of oncogenic virus caused rearrangment in the isoenzymatic spectra of lactate and malate dehydrogenases both in the nuclei and in the cytoplasm. these disturbances occur f ...1977907826
adenovirus type 12 dna sequences in primary hamster tumors.in five out of six primary hamster tumors induced by adenovirus type 12, less than 55% of the adenovirus type 12 genome is present. various fragments of the integrated viral dna were present in non-equimolar amounts.1977904032
transformation of a rat cell line by an adenovirus type 12 dna fragment. 1977898675
transcription of the genome of adenovirus type 12. iv. maps of stable late rna from productively infected human cells.from human kb cells productively infected with adenovirus type 12, mrna and stable nuclear rna were isolated late (42 h) after infection. using restriction endonuclease fragments of adenovirus type 12 dna, mrna and stable nuclear rna sequences were mapped on the viral genome. late after infection, preferentially the r (= rightward) strand is transcribed into stable nuclear rna, whereas the l (= leftward) strand is expressed only to a minor extent. adenovirus type 12-specific mrna originates from ...1977875133
multiple copies of human adenovirus 12 genomes are integrated in virus-induced hamster tumors.tumors induced in hamsters by highly oncogenic human adenovirus 12 contain multiple copies of 90 to 100% of the viral genome in an integrated form.1977853566
identification of early proteins induced by highly oncogenic human adenovirus 12 during lytic infection and in hamster tumors. 1977843353
integrated viral sequences in adenovirus type 12-transformed hamster cells.the physical state of the viral genome in four lines of hamster cells transformed by adenovirus type 12 (ad12) has been investigated. the four lines of transformed cells originated from hamster cells after infection with ad12 at multiplicities ranging from 5-350 plaque-forming units per cell. the dna from transformed cells has been restricted with the sal i endonuclease from streptomyces albus which cleaves adenovirus dna more frequently than dna from adenovirus-transformed hamster cells. thus a ...1977837440
tumor-specific transplantation antigen(s) of bovine adenoviruses.protection against bovine adenovirus type 3-induced primary or transplantable tumors was studied in hamsters immunized with bovine adenoviruses, human adenovirus type 12 (a-12), simian adenovirus type 7 (sa7), or chicken-embryo-lethal-orphan (celo) virus. newborn hamsters inoculated with 2.3 times 10-5 plaqueforming units of bovine adenovirus type 3 were given injections of bovine serotypes 1, 2, or 3 during the latent period of tumor development. no hamsters immunized with type 3 and only 47% o ...1975803562
detection and quantitation of adenovirus type 12 transforming dna segments and their application in etiological studies of human neoplasia.the oncogenic capacity of the tumour virus lies in a small region of the viral genome, and tumour cells and cells transformed by dna tumour viruses often contain only a part of the viral genome, the portion including the transforming gene(s). the detection and quantitation of these gene(s) in tumour cell dna can provide evidence for or against a possible etiological role of the virus in human neoplasia. in this communication, the isolation, purification and identification of the transforming seg ...1978730198
transcription map for adenovirus type 12 dna.the regions of the adenovirus type 12 genome which encode l- and r-strand-specific cytoplasmic rna were mapped by the following procedure. radioactive, intact, separated complementary strands of the viral genome were hybridized to saturating amounts of unlabeled late cytoplasmic rna. the segments of each dna strand complementary to the rna were then purified by s1 nuclease digestion of the hybrids. the arrangement of the coding regions of each strand was deduced from the pattern of hybridization ...1978702649
alterations in surface glycoproteins and level of sialyltransferase activity of human embryo kidney cells infected with oncogenic adenovirus type 12.human embryo kidney (hek) cells infected with adenovirus type 12 and its cytocidal mutants (cyt) synthesized different glycoproteins respectively on the cell surface at the early stage of infection. furthermore, a less and a highly tumorigenic cyt mutants synthesized different glycoproteins. the level of sialyltransferase activity in the microsomes of hek cells was increased when cells were infected with adenovirus type 12. it was confirmed that there was a positive correlation between the sialy ...1978694922
a variant of adenovirus 12 producing cytoplasmic accumulation of capsid proteins.a variant of adenovirus type 12 (r-ad12) has been isolated by infecting a clonal line of normal rat kidney cells (nrk) with wild-type adenovirus 12. although r-ad12 failed to produce infectious progeny virions when cycled a second time through nrk cells, it nevertheless retained the ability to code for virus structural proteins that accumulated in the cytoplasm.1978690616
morphological revertants of adenovirus type 12-transformed hamster cells.morphological revertants have been isolated from one line of adenovirus type 12-transformed hamster cells. this line, t637, is oncogenic in hamsters and contains multiple copies of the virus genome per cell. different parts of the virus genome are represented in non-stoichiometric amounts and the virus dna persists in the cells in an integrated form. the pattern of integrated virus genomes has been determined by the blotting technique. in the t637 line, morphological revertants arise spontaneous ...1978690612
patterns of integration of viral dna sequences in the genomes of adenovirus type 12-transformed hamster cells.the patterns of integration of the viral genome have been analyzed in four hamster cell lines transformed by adenovirus type 12 (ad12). it has previously been shown that in each of the cell lines ha12/7, t637, a2497-2 and a2497-3, the viral genome persists in multiple copies, and that different parts of the viral dna are represented non-stoichiometrically (fanning and doerfler, 1976). all four cell lines are oncogenic when injected into hamsters. the dna from each of the cell lines was extracted ...1978688383
adenovirus type 12 gene 401 function in transforming infection.the temperature-sensitive dna-minus mutant, h12ts401, transformed two to eight times more hamster embryo cells than wild-type 12 adenovirus at 38.5 degrees c, but was unable to establish transformation of cultures of hamster embryo brain and rat 3y1 cells at 41.5 and 40 degrees c, respectively. another h12ts406 dna-minus mutant was not defective in cell transformation at these restrictive temperatures. both mutants, however, induced t-antigen and cell dna synthesis after infection of 3y1 cells a ...1978671589
deletions and insertions in adenovirus type 12 dna after viral replication in vero cells. 1978664232
adenovirus type 12 tumor antigen. i. separation from dna polymerase alpha and immunoprecipitation of tumor-antigen polypeptides. 1978664211
isozymic forms of some energy metabolism enzymes during oncovirus-induced cell transformation.kinetic studies of changes in isozymic forms of hexokinase, lactate and malate dehydrogenase and in total hexokinase activity during viral carcinogenesis were carried out. the test systems were rat embryo fibroblasts infected with an oncogenic variant of human adenovirus type 12 and an infectious adenovirus type 6, intact ref cultures in different stages of growth (log and stationary phase), and hamster sarcoma a12 and rat reticulosarcoma 321-rrs cell cultures. molecular isozymic forms of the st ...1978658548
hyperthermia and host-cell reactivation of adenovirus 12.exposure of cultured human fibroblasts to hyperthermia delayed the host-cell reactivation of uv-irradiated human adenovirus type 12 (ad12). the experimental design consisted of irradiating human ad12 with uv doses ranging from 180 to 1800 ergs/mm2, infecting human cell populations at 37 degrees c, exposing the infected cells for 7 h to 39.5 degrees c and 41.8 degrees c, returning them to 37 degrees c and estimating the frequency of cells with intranuclear viral inclusion bodies (ib) 41 and 89 h ...1978657003
characterization of adenovirus type 12 tumour antigen produced in chick fibroblasts.tumor (t) antigen was characterized in non-permissive chick fibroblasts and permissive hep-2 cells infected with ad12 either in the presence or in the absence of cytosine arabinoside. antiserum against t antigen specifically immunoprecipitated two polypeptides of apparent mol. wt. 50 000 and 11 000.1978569186
abortive and transforming infection of rat cell line 3y1 by adenovirus type 12.human adenovirus type 12 underwent an abortive and transforming infection in clonal cultures of rat cell line 3y1. the frequency of transformation was proportional to the dose of input virus. the ratio of pfu to transforming units was 1.1 x 10(5).1978565416
purification of adenovirus type 12 tumor antigen from transformed hamster cells. 1977557257
susceptibility of ad12-transformed s (+) and s (-) mouse cells to cell-mediated immunity in vitro.adenovirus type 12 (ad12)-transformed mouse cells were examined for their susceptibility to cell-mediated immunity in vitro, with respect to the activity of the virus-specific surface (s) antigen in the cells. a transformed cell line, c57at1, was established from embryonic cells of c57bl/6 mice by ad12 infection. in fluorescent antibody tests, the transformed cells were positive for the s antigen when the cells were maintained as cultures, whereas when the cells were grown as tumors in animals t ...1979530102
transcription of the genome of adenovirus type 12. v. kinetic and size-class analyses of nuclear and messenger rna in productive infection.in human kb cells productively infected with adenovirus type 12 (ad12) the kinetics of synthesis of ad12-specific rna were investigated. using 2 h labelling periods, striking differences were observed in the time course and the rate of synthesis of virus rna comparing the nuclear, cytoplasmic and polysomal rna fractions. a protracted onset of virus rna synthesis was followed by an exponential increase between 15 and 40 h p.i.; reaching a maximum at 40 to 45 h p.i., the fraction of the newly synt ...1979528981
transforming dna sequences in rat cells transformed by dna fragments of highly oncogenic human adenovirus type 12.rat cell lines tranformed by viral dna fragments, ecori-c and hindiii-g, of adenovirus type 12 dna were analyzed for the viral transforming dna sequences present in cell dnas. cell lines transformed by the ecori-c fragment of adenovirus type 12 dna (leftmost 16.5% of the viral genome) contain most of the hindiii-g sequences of the hindiii-g fragment, but at a different frequency depending on the portions of the fragment. the sequence of the acci-h fragment of adenovirus type 12 dna (the left par ...1979501799
tumor-specific transplantation and surface antigen in cells transformed by the adenovirus 12 dna fragments.adenovirus type 12 (ad 12) tumor-specific transplantation antigen (tsta) and the surface (s) antigen were examined using rat cells transformed with ad 12 dna and its fragments. wy3 (3yl cells transformed with ad 12 whole dna), cyl (3yl cells transformed with the ecori-c fragment of ad 12 dna), and gy cells (3yl cells transformed with the hindiii-g fragment of ad 12 dna) contained tsta and s antigen, but hy cells (3y1 cells transformed with the bpai-h fragment of ad12 dna) did not. these results ...1979494494
adenovirus type 12 tumor antigen. ii. immunoprecipitation of protein kinase from infected and transformed cells by antisera to t antigen and some normal rat sera. 1979494492
in vitro translation of adenovirus type 12-specific mrna isolated from infected and transformed cells.the early and late gene products of human adenovirus type 12 (ad12), as well as the viral proteins synthesized in an ad12-transformed cell line, were identified by translation of viral mrna in an in vitro protein-synthesizing system. cytoplasmic rna was isolated from permissive kb or nonpermissive bhk cells infected with ad12 and from ad12-transformed ha12/7 cells. virus-specific rna was selected by hybridization to ad12 dna covalently bound to cellulose. viral rna was then translated in a fract ...1979480453
a rapid screening for the specific dna sequence: analysis of transforming dna segments in adenovirus-transformed cells.the viral dna sequences in cells transformed by adenovirus type-12 (ad12) dna fragments were investigated by spot hybridization, a detection by autoradiography of nucleic acid hybrids formed between cell dnas spotted on a membrane filter and various nick-translated ad12 dna fragments. in cy1 cell line, a rat cell line transformed by the ecori-c fragment (left hand 16%), all of the hindiii fragments included in the ecori-c fragment are shown to be present. in gy1 cell line, a rat cell line transf ...1979467887
adenovirus type 12 va rna. i. synthesis in productive infection and gene mapping. 1979462796
[brain tumors induced by human adenovirus type 12 in c3h/he mice (author's transl)]. 1979454556
cell origin of human adenovirus type 12-induced subcutaneous tumor in syrian hamsters.single subcutaneous inoculation of human adenovirus type 12 (ad.12), 0.05-0.1 ml of 10(8.0) tcid50 hek cells/0.1 ml, was made on the back of 0-day-old hamsters. in 21 of 25 hamsters (84.0%), multiple solid tumors developed close to the inoculation site within 3 months. no control hamsters developed tumors. tumor histopathology revealed the characteristic homer wright rosettes of neuroblastoma. ad. 12-specific tumor antigens were demonstrable in both the primary and the cultured tumor cells by th ...1979442984
requirement of adenovirus type 12 gene 401 function for initiation of virus dna synthesis.the highly oncogenic human adenovirus type 12 temperature sensitive mutant. h12ts401, is unable to maintain the growth characteristics of transformed cells at the non-permissive temperature. in lytic infection, the 401 gene function is required to produce virus dna. in the present study, virus dna synthesized in ts401-infected human cells after temperature shift-up was characterized. no apparent suppression of dna chain elongation or ligation occurs at the non-permissive temperature, but, as sho ...1979430034
identification of adenovirus type 12 candidate transformation proteins by radioimmunoprecipitation with antisera to ecori-c-fragment transformed cells. 1979375576
comparative study by immunofluorescence of t and p antigens induced by adenovirus type 12 in permissive and nonpermissive cells.the development of adenovirus type 12 t antigen and of the complex of antigenic early proteins designated as p antigen was studied by immunofluorescence in productively infected kb cells and abortively infected rk-13 cells. t antigen is detected in both cell types very early in infection. in kb cells it presents the well known pattern of nuclear dots and flecks but in rk-13 cells at the time of maximum abundance, 18 hours p.i., t antigen forms a net of long filaments that fills the nucleus. late ...1978367317
helper factor(s) for growth of adeno-associated virus in cells transformed by adenovirus 12.evidence is presented that a helper factor(s) for growth of adeno-associated virus (aav) is present in cells transformed by adenovirus type 12 (ad12). the growth of aav was observed in heterokaryons formed by fusion of human kb and ad12-transformed rodent cells by using ultraviolet-inactivated sendai virus without coinfection of cells with adenovirus. the presence of the helper factor(s) for aav growth in rat cells transformed by the ecori-c fragment or the hindiii-g fragment of ad12dna suggests ...1977337298
retinoblastoma-like neoplasm induced in c3h/bifb/ki strain mice by human adenovirus serotype 12.eighty newborn c3h/bifb/ki strain mice received a single intraocular inoculation of 0.002--0.003 ml of 10(8.0) tcid 50/0.1 ml human adenovirus 12 (ad 12), within 24 h after birth. forty mice survived and in seven of these (17.5%) a solid retinoblastomalike neoplasm developed between 64 and 236 days. the tumors have been successfully cultured and also transplanted subcutaneously into syngeneic hosts. morphologically, all tumors revealed characteristic features of retinoblastoma associated with th ...1977331842
physico-chemical characteristics of interferons induced by human adenovirus in chick fibroblasts and leucocytes.the physico-chemical characteristics of interferons with different anti-viral activities produced in chick fibroblast cells and leucocytes in response to the human adenovirus type 12 were investigated. the molecular weights of interferons produced by chick fibroblasts and leucocytes were similar: the main anti-viral activity was found at 27000 and 32000 and a low-titered shoulder at 28000 and 23000 respectively. under our experimental conditions no oligomeric structure of interferons could be de ...1975241243
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