Publications
| Title | Abstract | Year(sorted descending) Filter | PMID Filter |
|---|
| topographical and conformational epitopes of bovine papillomavirus type 1 defined by monoclonal antibodies. | monoclonal antibodies (mabs) were generated against sodium dodecyl sulfate-disrupted bovine papillomavirus type 1 (bpv-1). when screened by enzyme-linked immunosorbent assay (elisa) on intact and disrupted bpv-1, -2, and deer papillomavirus, three patterns of reactivity were defined: reactivity only with intact virus, with both intact and disrupted virus, and only with disrupted virus. on the basis of elisa results, the topographical location and requirement for conformation for immunoreactivity ... | 1987 | 2446044 |
| stable expression of recombinant factor viii molecules using a bovine papillomavirus vector. | the bleeding disorder in hemophilia a results from a deficiency or abnormality of factor viii (fviii), a member of the coagulation cascade. fviii is a large glycoprotein (approximately 350,000 daltons) that is activated by a series of proteolytic cleavages. during activation, a large internal domain (b domain) is removed, resulting in an active complex comprised of the amino and carboxyl subunits of the parental molecule. using a bovine papillomavirus expression vector system, we have establishe ... | 1987 | 2448100 |
| transcriptional regulation of the human papillomavirus-16 e6-e7 promoter by a keratinocyte-dependent enhancer, and by viral e2 trans-activator and repressor gene products: implications for cervical carcinogenesis. | the transcriptional promoter of the candidate e6-e7 transforming gene region of human papillomavirus (hpv)-16 (p97) was active in transiently transfected cervical carcinoma cells when linked to the hsv-1 tk or bacterial cat genes. sequences 5' to p97 contain a short enhancer element responding to cellular factor(s) in uninfected human foreskin keratinocytes and in cervical carcinoma cells, but not in human or animal fibroblasts. the e2 trans-activator products of hpv-16 or of the related bovine ... | 1987 | 2448139 |
| calmodulin as a regulator of cell growth and gene expression. | 1987 | 2850611 | |
| calmodulin is involved in regulation of cell proliferation. | a chicken calmodulin (cam) gene has been expressed in mouse c127 cells using a bovine papilloma virus (bpv)-based vector (bpv-cm). the vector-borne genes produce a mature mrna of the expected size that is present on cytoplasmic polyribosomes. in clonal cell lines transformed by bpv-cm, expression of the cam gene produced cam levels 2- to 4-fold above those observed in cells transformed by bpv alone. increased intracellular cam caused a reduction of cell cycle length that is solely due to a reduc ... | 1987 | 2832147 |
| cross-hybridization and relationships of various papillomavirus dnas at different degrees of stringency. | cloned dnas of 21 different papillomaviruses which naturally infect mammals and one bird papillomavirus were compared for relative homology by southern blot hybridization. blots were carried out under low (tm-40 degrees), medium (tm-33 degrees), and high (tm-22 degrees) stringency conditions. at higher stringency, human papillomaviruses cross-hybridized with each other reflecting species-specific similarities. bovine papillomavirus types 1, 2, 5, european elk papillomavirus, and deer papillomavi ... | 1987 | 2832347 |
| integration and transcription of human papillomavirus type 6 recombinant dna in mouse cells. | human papillomavirus (hpv) dna is found in nature mostly in an episomal form. however, in permanent cell lines established from cervical carcinomas in which hpv sequences are present, they are usually integrated in the host genome. in vitro studies of hpv have been hampered because of the difficulty of stably maintaining hpv sequences in transfected cells. we have cloned the entire hpv6 genome into three vectors: pml2, a derivative of pbr322 lacking the "poison sequences"; p142-6, a plasmid cont ... | 1987 | 2829459 |
| the bovine papillomavirus genome and its uses as a eukaryotic vector. | 1987 | 2829815 | |
| structure and genetic expression of papillomaviruses. | this article reviews the physical structures, genetic organization, expression, and regulation of papillomaviruses. in view of the extensive characterization of cellular transformation and viral functions that have been achieved in experimentally infected animals and in transformed cell cultures, the bovine papillomavirus type 1 (bpv-1) and shope cottontail rabbit papillomavirus (crpv) are compared and contrasted with the human papillomaviruses. | 1987 | 2829072 |
| multiple cis-active elements in the long control region of bovine papillomavirus type 1 (bpv-1). | a 1.0 kb region of the bpv-1 genome (the long control region, lcr), contains controls for transcription and the origin of replication. transcription directed by the lcr is activated by the viral encoded e2 protein. to define the essential cis acting elements that are required to control transcription we have constructed a series of deletions throughout the lcr. we have identified three important domains in the lcr, two of which respond to e2. we have analysed the ability of small subcloned regio ... | 1987 | 2827118 |
| the bpv1-e2 trans-acting protein can be either an activator or a repressor of the hpv18 regulatory region. | the human papillomavirus 18 (hpv 18) long control region contains promoter and enhancer elements whose activity is restricted to several human cell lines of epithelial origin. this enhancer possesses a considerable constitutive activity which is further stimulated in the presence of the e2 trans-activating protein of bovine papillomavirus 1 (bpv1). surprisingly the same bpv1 protein strongly repressed transcription from the genuine hpv18 enhancer-promoter dna sequences. we suggest that binding o ... | 1987 | 2828029 |
| detection of dna of human papillomavirus types 6/11 and 16/18 in cell scrapings of the uterine cervix by filter in situ hybridisation. correlation with cytology, colposcopy and histology. | the application of filter in situ hybridisation (fish) to detect the presence of the dna of human papillomavirus genotypes 6/11 and/or 16/18 in cell scrapings of the uterine cervix of 248 women in western australia is described. the results obtained by fish are related to cervical dysplasia as assessed by cytology, colposcopy and histology. the detection of hpv infection was more sensitive and specific by fish than by either histological/cytological evidence of an hpv cytopathic effect (koilocyt ... | 1987 | 2826222 |
| messenger rnas from the e1 region of bovine papillomavirus type 1 detected in virus-infected bovine cells. | bovine papillomavirus type 1 dna replicated to a high copy number in virus-infected bovine fibroblasts. infected bovine cells were therefore used as a source of rna for northern blotting analysis to search for viral transcripts hybridizing to the e1 gene region, implicated in viral dna replication. cytoplasmic polyadenylated rna preparations contained at least five different e1-region transcripts, ranging from 1200 to approximately 4500 nucleotides in length. all of these species contained seque ... | 1987 | 2825116 |
| replication of plasmids derived from bovine papilloma virus type 1 and epstein-barr virus in cells in culture. | the major components encoded by bpv-1 and ebv that act in plasmid replication of these viral dnas in latently infected cells are now known. the minimal dna sequences required in cis have been delineated, and the genes whose products are required in trans have been identified. the only required trans-acting gene of ebv, ebna-1, has been shown to bind specifically to the cis-acting element, orip. the current advanced understanding of plasmid replication of mtdna and sv40 dna is likely to aid in th ... | 1987 | 2825737 |
| papillomas and cancer in cattle. | papillomaviruses induce hyperproliferation of epithelial cells of the skin or mucosa (papillomas), and certain types can also infect fibroblasts. they are a very heterogeneous group of viruses, and individual types are associated with specific lesions. the papillomas are mostly benign but some tumours may eventually undergo malignant conversion when genetic or environmental factors are involved. in cattle, bovine papillomavirus type 4 (bpv-4) is the causative agent of papillomas of the alimentar ... | 1987 | 2825987 |
| mouse cell lines that use heat shock promoters to regulate the expression of tissue plasminogen activator. | the promoters from drosophila and human 70,000-dalton heat shock protein (hsp70) genes were linked to human tissue plasminogen activator (tpa) cdna. mouse c127 cells were transformed with bovine papilloma virus (bpv) vectors carrying the hybrid hsp70/tpa genes. stable bpv-transformed cell lines were selected and analyzed for tpa expression before and after heat shock. in most cell lines, there was a low level of tpa production even in the absence of heat shock or other obvious stress. after heat ... | 1987 | 2820678 |
| isolation and characterization of minichromosome particles that contain a glucocorticoid-modulated promoter. | a procedure for the enrichment of minichromosomes, composed of bovine papilloma virus and the long terminal repeat element of the mouse mammary tumor virus (mtv), from isolated nuclei is described. up to 60% of the minichromosomes were extracted as nucleoprotein particles. these particles sediment in sucrose gradients as 160s complexes. hormone-labeled glucocorticoid receptor co-purifies with these complexes in a specific fashion. between four and six molecules of receptor are bound per minichro ... | 1987 | 2821487 |
| optimizing gene expression in bpv-transformed cells: effects of cell type on enhancer/promoter interaction. | we have compared several combinations of enhancers and promoters in expressing the chloramphenicol acetyl transferase gene in transient assays, in mouse c127, the most widely used host cell for the bovine papilloma virus (bpv) expression vector. of the various combinations tested, the unit comprised of the sv40 enhancer and adenovirus type 2 major late promoter (mlp) was the most active in bpv transformed c127 cells. we further demonstrate that untransformed and bpv transformed c127 cells respon ... | 1987 | 2821493 |
| genetic and biochemical definition of the bovine papillomavirus e5 transforming protein. | mutations surrounding the first methionine codon of the e5 transforming gene of bovine papillomavirus (type 1) were analyzed for their effect on cellular transformation and on the synthesis of the 7-kd e5 polypeptide. frameshift mutations upstream of this methionine codon (bp 3879) affect neither transforming activity nor the ability to synthesize full-size e5 protein. in contrast, frameshift mutations distal to this position result in the inhibition of cell transformation and prevent synthesis ... | 1987 | 2822390 |
| skin cancer and papillomaviruses in cattle. | we examined proliferative lesions on the sun-exposed, unpigmented skin of 13 cattle. ages of animals at first examination ranged from 4 to 15 years, and 4 were observed for from one to 3 years, during which time progression to malignancy occurred in 2 of them. early lesions consisted of keratin scales and horns; histology showed underlying acanthosis and hyperkeratosis. advanced lesions were either squamous cell carcinomas or basaloid tumours with sebaceous and/or squamous differentiation; some ... | 1987 | 2822781 |
| reindeer papillomavirus transforming properties correlate with a highly conserved e5 region. | a papillomavirus was isolated from the epithelial layer of a cutaneous fibropapilloma on a swedish reindeer (rangifer tarandus). reindeer papillomavirus (rpv) is morphologically indistinguishable from other papillomaviruses, but the restriction enzyme cleavage pattern of its genome is different. no sequence homology was detected between rpv dna and the dnas of bovine papillomavirus type 1 (bpv-1) and avian papillomavirus when hybridization was performed under stringent conditions. however, the r ... | 1987 | 2822949 |
| proteins present in bovine papillomavirus particles. | analysis by two-dimensional gel electrophoresis and silver staining of heavy full, light full, and empty bovine papillomavirus particles has shown that the major capsid protein l1 is highly modified. besides exhibiting at least 13 isoelectric point variants of approximately the same molecular mass (54 kilodaltons), it is suggested that an additional heavier protein chain (69 kilodaltons) is also derived from l1 by glycosylation. these modifications may stabilize the particle structure. treatment ... | 1987 | 2822965 |
| stimulation of cellular dna synthesis by wild type and mutant bovine papillomavirus dna. | microinjection of recombinant plasmids containing bovine papillomavirus type 1 dna into the nuclei of mouse c127 cells results in the stimulation of cellular dna synthesis. mutations in the viral e2 gene have no apparent effect on this activity even though the same mutations prevent efficient c127 cell focus formation and inhibit transactivation by this gene. | 1987 | 2823817 |
| expression of human uterine tissue-type plasminogen activator in mouse cells using bpv vectors. | human tissue-type plasminogen activator (t-pa) cdna was cloned from uterine tissue and engineered in expression vectors for production in mouse c127 cells. the vectors consisted of the bovine papilloma virus-1 (bpv-1) genome and t-pa transcriptional unit with a mouse metallothionein (mt-1) promoter at the 5' end and mt-1 genomic sequences or sv40 early introns and polyadenylation signals at the 3' end. analysis of the expression vectors transfected into cells revealed that t-pa is expressed 100- ... | 1987 | 2824147 |
| the p39 promoter of minute virus of mice directs high levels of bovine growth hormone gene expression in the bovine papilloma virus shuttle vector. | the promoter of the capsid-coding genes of the autonomous parvovirus minute virus of mice (mvm) is shown to drive high levels of expression of the heterologous bovine growth hormone (bgh) gene in a bovine papilloma virus (bpv)-based shuttle vector. the expression of bgh directed by the mvm p39 promoter was, on average, higher than that obtained from the widely used metallothionein promoter. these results indicate that the mvm-p39/bpv shuttle vector will be generally useful for the high-level exp ... | 1987 | 2824293 |
| human cytomegalovirus (hcmv) enhances bovine papilloma virus (bpv) transformation in vitro. | infection of nih 3t3 cells with a combination of hcmv and bpv resulted in more foci than infection with bpv alone. foci were microscopically apparent at 4 days in the mixed infection and did not appear until 2 days later in the cultures infected with bpv alone. the enhancement was abolished by heat inactivation of the hcmv and also when the hcmv was replaced by a "mock inoculum." southern blot analysis of cellular dna from transformed cells showed a similar amount of extrachromosomal bpv dna in ... | 1987 | 2824682 |
| mutational analysis of the 3' open reading frames and the splice junction at nucleotide 3225 of bovine papillomavirus type 1. | functional analysis of the 3' open reading frames (orfs) of bovine papillomavirus type 1 (bpv-1) has been complicated by the organization of that part of the genome. a region between nucleotides (nt) 3173 and 3551 contains three overlapping orfs (e2, e3, and e4), as well as a 3' splice junction at nt 3225 which is used by many of the bpv-1 transcripts. to more clearly assign functions to specific orfs in this region, single-base substitution mutations were generated which introduced translationa ... | 1987 | 2824822 |
| transcriptional organization of bovine papillomavirus type 4. | seven virus-specific rna transcripts have been identified in tumours induced by bovine papillomavirus type 4 (bpv-4). the rnas measured 4.2, 3.6, 3.0, 2.8, 1.9, 1.6 and 1.0 kilobases (kb). they were mapped on the viral genome by northern blot hybridization to subgenomic probes, by cdna hybridization to viral dna fragments and by s1 analysis of unlabelled and 3' and 5' end-labelled dna fragments. all the rna species are transcribed from the same dna strand, are polyadenylated and with the excepti ... | 1986 | 2878058 |
| replication of the bovine papillomavirus type 1 genome; antisense transcripts prevent episomal replication. | a subgenomic fragment, representing 69% of the bovine papillomavirus type 1 (bpv-1) genome, has the capacity to transform mouse c127 cells in vitro and to replicate episomally in these cells. in the present study we have cloned this bpv-1 fragment between two retrovirus-derived long terminal repeats (ltrs) in the two possible orientations. the constructs were designated pmr and pml. the pmr construct contained the bpv-1 genome in the same transcriptional orientation as that of the ltrs whereas t ... | 1986 | 2438189 |
| analysis of pp60c-src protein kinase activity in hamster embryo cells transformed by simian virus 40, human adenoviruses, and bovine papillomavirus 1. | we have examined the effect of dna tumor virus transformation of primary hamster embryo cells on the tyrosyl kinase activity of pp60c-src. our present study demonstrates that some clones of hamster embryo cells transformed by simian virus 40, adenovirus type 2, adenovirus type 12, or bovine papillomavirus 1 can possess elevated pp60c-src kinase activity when compared with normal hamster embryo cells. however, other clones of hamster embryo cells transformed by these same viruses were found to ha ... | 1986 | 2416954 |
| [papilloma viruses: group-specific antigens within lesions of the oral mucosa]. | the present study was undertaken with purpose to investigate the relationships between intraepithelial proliferations of malpighian mucosa and the presence of group specific papilloma virus antigens. the investigations allowing to give viral types or subtypes, the hybridization technics, are very heavy and not disponible in routine practice. the detection of widely distributed genus specific hpv antigen using pap immunohistochemical labeling in different lesions and their association with displa ... | 1986 | 2421394 |
| papillomaviruses and interferon. | papillomaviruses are infectious agents which cause benign tumours, or warts, of cutaneous, uterine cervical and laryngeal epithelia. these infections are very common, yet no uniformly effective therapy exists. current treatments do not selectively inhibit viral processes but destroy the infected epithelial cells. since interferons have antiviral effects in vivo and in vitro, it was hypothesized that they might be useful for treating papillomavirus-induced conditions. interferons have now been de ... | 1986 | 2424679 |
| in vitro methylation of bovine papillomavirus alters its ability to transform mouse cells. | bovine papillomavirus (bpv) was methylated in vitro at either the 29 hpaii sites, the 27 hhai sites, or both. methylation of the hpaii sites reduced transformation by the virus two- to sixfold, while methylation at hhai sites increased transformation two- to fourfold. dna methylated at both hpaii and hhai sites did not differ detectably from unmethylated dna in its efficiency of transformation. these results indicate that specific methylation sites, rather than the absolute level of methylated c ... | 1986 | 2431294 |
| physical state, expression and regulation of two glucocorticoid-controlled genes on bovine papilloma virus vectors. | we have studied the extrachromosomal maintenance and the transcription regulation of two glucocorticoid-inducible genes on bovine papilloma virus (bpv) vectors in c127 mouse fibroblasts. these genetic elements were the rat tryptophan oxygenase (toase) gene promoter, which is active in vivo only in hepatocytes, and the long terminal repeat of the mouse mammary tumor virus (mmtv-ltr). from both genes, fusions of the 5'-flanking region of the transcription unit to the bacterial gene for chloramphen ... | 1986 | 3012094 |
| structure of bovine papillomavirus type 1 dna in a transformed mouse cell line. | linearized bovine papillomavirus type 1 (bpv-1) dna was introduced into mouse c127 cells, where it recircularized and replicated as an intact monomeric, extrachromosomal circular form in the resulting transformants. these cells contained a mixture of complex high molecular weight forms that were converted to a linear form of approximately bpv-1 size upon digestion with an enzyme that cuts once within the bpv-1 genome. further analysis of one of these cell lines revealed that these high molecular ... | 1986 | 3012096 |
| transient replication of bovine papilloma virus type 1 plasmids: cis and trans requirements. | a transient assay has been used to study bovine papilloma virus type 1 (bpv-1) replication. we show that bpv-1 early replication occurs faster than cellular dna synthesis. initial replication events are dependent on a gene product(s), encoded by the bpv-1 e1 open reading frame. mutational analysis of the viral upstream regulatory region shows the requirement of two domains in cis for replication. domain one, located outside of the viral 69% transforming fragment, is an enhancer-like activity and ... | 1986 | 3012521 |
| criteria for establishing that a virus is oncogenic. | to prove that a particular infectious agent causes a disease is much more difficult in human subjects than in other animals for both ethical and practical reasons. where the disease is a malignant tumour with a long latent period the situation is even more difficult. for these reasons, it is often necessary to concentrate in the first instance on association of the virus with the disease, and this is discussed in the context of papillomaviruses. association of a virus with a tumour may occur for ... | 1986 | 3013518 |
| papillomavirus infection in cattle: viral and chemical cofactors in naturally occurring and experimentally induced tumours. | six different types of bovine papillomavirus (bpv-1 to bpv-6) have been identified and classified into two subgroups: subgroup a, which induce fibropapillomas, and subgroup b, which induce true epithelial papillomas. bpv-4, a member of subgroup b, is the aetiological agent of papillomas of the upper alimentary canal, which can become a focus for transformation to squamous-cell carcinomas in animals feeding on bracken fern. strong circumstantial evidence suggests that the progression to malignanc ... | 1986 | 3013519 |
| immunization against bovine papillomavirus infection. | the two large open reading frames denoted l1 and l2 in the non-transforming region of the bovine papillomavirus type 1 (bpv-1) genome have been molecularly cloned to expression in escherichia coli. antisera against the e. coli-derived l1 and l2 protein reacted with bpv-1 in both enzyme-linked immunosorbent assays and immunoprecipitation reactions. neutralization of bpv-induced transformation of mouse c127 cells was demonstrated most consistently with antisera against the l1 protein. e. coli-deri ... | 1986 | 3013520 |
| organization and expression of the genome of bovine papillomavirus type 1. | the viral mrnas present in c127 cells transformed by bovine papillomavirus type 1 (bpv-1) have been mapped by a variety of techniques, including s1 nuclease analysis, northern blot analysis, primer extension and electron microscopic heteroduplex analysis. the results reveal a very complex mrna pattern, comprising at least five types of spliced cytoplasmic mrnas. both unspliced and partially processed nuclear rna species have also been identified. the transforming region of bpv-1 contains several ... | 1986 | 3013523 |
| classification of the papillomaviruses--mapping the genome. | papillomaviruses form one genus of the papovaviridae family. they share common antigenic determinants and their dnas cross-hybridize under conditions of low stringency. the classification of papillomaviruses is at present based on the host range and the relatedness of the nucleic acids. isolates are considered independent types if there is less than 50% cross-hybridization in the liquid phase according to a standard protocol. at least 31 human and six bovine papillomavirus types can be different ... | 1986 | 3013524 |
| papillomavirus transforming functions. | the bovine papillomavirus type 1 (bpv-1) has served as a model for unravelling the molecular genetics of the papillomaviruses. bpv-1 transformation of rodent cells in tissue culture has provided a means to study the viral functions involved in latent infection of cells and in the induction of cellular proliferation functions. bpv-1 has been shown to encode two independent transforming genes, each of which can induce cellular transformation in susceptible rodent cells. these two genes apparently ... | 1986 | 3013525 |
| the bovine papillomavirus replicon. | the bovine papillomavirus genome contains two cis-acting sequences which can serve as signals for replication. at least three virally encoded genes seem to be involved in plasmid replication: e6, e6/7 and e1. mutations in either the e6 or the e7 open reading frame create plasmids that are maintained at a low copy number per cell. mutations in the e1 open reading frame are absolutely lethal to replication. complementation experiments show that these mutations define separate genes. experiments ar ... | 1986 | 3013526 |
| the e5 transforming gene of bovine papillomavirus encodes a small, hydrophobic polypeptide. | bovine papillomavirus (bpv-1) contains two independent transforming genes that have been mapped to the e5 and e6 open reading frames (orf's). the e5 transforming protein was identified by means of an antiserum against a synthetic peptide corresponding to the 20 cooh-terminal amino acids of the e5 orf. the e5 polypeptide is the smallest viral transforming protein yet characterized; it had an apparent size of 7 kilodaltons. the transforming polypeptide is encoded entirely within the second half of ... | 1986 | 3014660 |
| comparison of methods for introducing vectors based on bovine papillomavirus-1 dna into mammalian cells. | the intracellular structure of several vectors based on bpv-1 dna has been analyzed following transfection into mouse c127 cells by the calcium phosphate method or, for the first time, by microinjection directly into the nucleus. it is shown that the method of introduction markedly affects the fate of a bpv-1 based vector. in general, microinjection appears to do little damage to dna and is more likely to result in a vector replicating extrachromosomally as a monomeric structure of the same size ... | 1986 | 3016916 |
| aetiology of enzootic haematuria. | the precise aetiology of enzootic haematuria in cattle remains unknown. the involvement of bracken fern (pteridium aquilinium) appears certain because of the close association between bracken fern infested farms and enzootic haematuria. several toxic principles have been identified but the main carcinogenic element remains to be conclusively demonstrated. more recently, bovine papilloma virus has been implicated in the aetiology of enzootic haematuria. its possible interaction with bracken fern ... | 1986 | 3016971 |
| negative control of dna replication in composite sv40-bovine papilloma virus plasmids. | to identify dna sequences that function in the control of dna replication, we designed a hybrid replicon consisting of linked sv40 and bpv dna sequences. in the composite sv40-bpv plasmid negative control encoded by bpv is dominant over the uncontrolled replication encoded by the positive factor, sv40 t antigen. using a transient replication assay, we show that replication control requires three bpv elements. two cis-acting sequences are closely linked to bpv replication origins. a third trans-a ... | 1986 | 3017566 |
| repression of bovine papilloma virus replication is mediated by a virally encoded trans-acting factor. | cells transformed with bovine papilloma virus type 1 mutants in the e6 or e6/7 genes are resistant to high-copy-number amplification of wild-type dna after supertransfection. transient and stable replication assays demonstrate this effect. if the supertransfected dna has a mutation in a newly defined gene (m), this cellular immunity to high-copy-number replication is overcome, resulting in transient replication of the input dna. in contrast, the resident plasmid does not participate in amplifica ... | 1986 | 3017567 |
| cleavage of vimentin in dense cell cultures. inhibition upon transformation by type 5 adenovirus. | the analysis on two-dimensional isoelectric focusing and sds polyacrylamide gels (2d gels) of the triton x-100 and high salt-insoluble fraction of fibroblast cell lines, certain epithelial cell lines and granulosa cells revealed various amounts of a vimetin cleavage product, with a more basic pi and with a mw (1,500-2,000) lower than that of intact vimentin. this cleavage product of vimentin which constituted as much as 30% of the total vimentin in an established rat embryo fibroblast cell line ... | 1986 | 3017738 |
| the expression of human papillomavirus type 18 e6 protein in bacteria and the production of anti-e6 antibodies. | human papillomavirus type 18 (hpv-18) has recently been closely linked with human malignant cervical lesions. the early region of the genome of the related bovine papillomavirus (bpv) has been shown to be important for the production of the transformed phenotype. bpv e6 has been shown to be a transforming protein. we report the primary structure of the hpv-18 e6 open reading frame and its predicted amino acid sequence. both e6 protein and e6-beta-galactosidase fusion protein were synthesized in ... | 1986 | 3018129 |
| organization and expression of the transforming region from the european elk papillomavirus (eepv). | the nucleotide sequence of the early (transforming) region from the european elk papillomavirus (eepv) double-stranded dna has been determined together with flanking regions. the established sequence, which is 5732 bp long, shows that the genome of eepv is closely related to the previously sequenced bovine papillomavirus type 1 (bpv-1) and deer papillomavirus (dpv) genomes. seven open reading frames (orfs), designated e1-e7, were identified in similar positions as in the bpv-1 genome. the e1 and ... | 1986 | 3034730 |
| duplication of a viral enhancer sequence improves the stability of a vector based on bpv-1 dna. | various recombinant constructions involving bovine papillomavirus type 1 (bpv-1) dna and bacterial plasmids have been tested for their ability to transform mouse c127 cells and replicate as intact extrachromosomal monomeric structures. when bpv-1 dna was linked to pbr328, pat153 or derivatives of these plasmids lacking the 344 bp hindiii-bamhi fragment or another small segment, the resulting vectors replicated in c127 cells as high molecular weight structures and, in some cases, deleted extrachr ... | 1986 | 3026114 |
| monoclonal antibodies to genus- and type-specific papillomavirus structural antigens. | monoclonal antibodies against sds-disrupted bovine papillomavirus type 1 (bpv1) were obtained from hybridomas prepared by fusing mouse myeloma cell line p3x63ag8u1 with spleen cells from immunized balb/c mice. six hybridoma cell lines were obtained after testing supernatant fluids for positivity by the enzyme-linked immunosorbent assay using the immunogen as antigen and by indirect immunofluorescence (if) on frozen sections of bpv1-induced bovine fibropapillomas. monoclonal antibodies (au1-au6) ... | 1986 | 3009351 |
| properties of intracellular bovine papillomavirus chromatin. | episomal nucleoprotein complexes of bovine papillomavirus type 1 (bpv-1) in transformed cells were exposed to dnase i treatment to localize hypersensitive regions. such regions, which are indicative for gene expression, were found within the noncoding part of the genome, coinciding with the origin of replication and the 5' ends of most of the early mrnas. however, there were also regions of hypersensitivity within the structural genes. these intragenic perturbations of the chromatin structure co ... | 1986 | 3009863 |
| expression of the three influenza virus polymerase proteins in a single cell allows growth complementation of viral mutants. | transformed cell lines derived from murine c127 cells were constructed that express the influenza virus rna-dependent rna polymerase proteins (pa, pb1, and pb2). cell lines that express only one or all three of the proteins were tested for their ability to complement temperature-sensitive viral mutants incubated at the nonpermissive temperature. two cell lines were isolated that express all three polymerase genes and complement the growth of pb2 temperature-sensitive mutants at the nonpermissive ... | 1986 | 3010315 |
| human papillomaviruses and cancer. | 1986 | 3011085 | |
| e5 open reading frame of bovine papillomavirus type 1 encodes a transforming gene. | we have previously shown that the early region of the bovine papillomavirus type 1 genome contains two nonoverlapping segments that can independently induce the morphological transformation of cultured cells. the transforming gene from the 5' end of the early region is encoded by the e6 open reading frame. the second transforming segment was previously localized to a 2.3-kilobase fragment (2.3t) from the 3' end of the early region. to determine which of the four open reading frames (e2, e3, e4, ... | 1986 | 3001335 |
| chromosome abnormalities in bovine papillomavirus type 1-transformed syrian hamster cells before and after tumor formation. | syrian hamster embryonic fibroblasts transformed by infection with bovine papillomavirus type 1 cause tumors when inoculated into hamsters. chromosome examinations revealed several abnormal clones in the transformed fibroblasts and a variety of additional markers in three tumors. only one aberration, trisomy 11, was present in each cell. the extra chromosome #11, thus, is considered to be essential for tumor formation in this model system. | 1986 | 3002604 |
| viral dna sequences detected in a hamster liposarcoma induced by bovine papillomavirus type 4. | following intradermal inoculation of bovine papillomavirus type 4 (bpv-4) into a syrian hamster, a liposarcoma developed at the inoculation site 20 months later. the dna of this tumour contained multiple copies of the bpv-4 genome which existed in a free unintegrated state. unintegrated viral dna and viral dna isolated from virus particles from bovine alimentary tract papillomas revealed identical cleavage patterns with cpg methylation-resistant and -sensitive restriction enzymes: apparently the ... | 1986 | 3003234 |
| nonsense mutation in open reading frame e2 of bovine papillomavirus dna. | oligonucleotide-directed mutagenesis was used to construct a nonsense mutation in open reading frame (orf) e2 of bovine papillomavirus dna. a single base substitution mutation was constructed which converted a tac codon into a tag amber stop codon at a position in the orf that did not overlap with any other viral orfs. full-length viral dna containing the mutation induced only approximately 2% of the transformed foci of mouse c127 cells that were induced by wild-type dna. in a different transfor ... | 1986 | 3003380 |
| human papilloma virus and cervical cancer. | 1986 | 3003916 | |
| molecular cloning and characterization of human papillomavirus type 7 dna. | human papillomavirus type 7 (hpv-7) was first described in 1981 but so far could not be molecularly cloned. it has been found almost exclusively in hand warts of butchers. we have cloned the complete genome in pbr 322, established its physical map, demonstrated the colinear genome organization with hpv-18 and analyzed the degree of homology with other hpv types and bovine papillomavirus (bpv) types. in order to investigate whether hpv-7 might be a so far unidentified bovine virus, we screened 37 ... | 1986 | 3004029 |
| translation of open reading frame e5 of bovine papillomavirus is required for its transforming activity. | a series of mutations in open reading frame (orf) e5 of bovine papillomavirus type 1 has been constructed to determine whether this putative gene is required for in vitro oncogenic transformation by viral dna. frameshift mutations at either of two different positions located exclusively in orf e5 cause a substantial reduction in the ability of the cloned viral dna to induce the appearance of transformed foci of mouse c127 cells. a genetic mapping experiment with one of the mutants indicates that ... | 1986 | 3006073 |
| genetic analysis of the 3' early region transformation and replication functions of bovine papillomavirus type 1. | cell transformation by bpv-1 is dependent on sequences confined to a region comprising only 69% of the viral dna. analysis of this subgenomic fragment of the viral genome has revealed a composite of functions. to further study this region of the bpv-1 genome, we constructed mutants affecting the 3' half of the transforming region. these mutations have revealed a plasmid maintenance function for the e2 orf and a requirement that the 3' half of e5 be intact for in vitro mouse cell transformation. ... | 1986 | 3006336 |
| bovine papillomavirus genome elicits skin tumours in transgenic mice. | transmission of the bovine papillomavirus-1 (bpv-1) genome through the mouse germ line results in the heritable formation of fibropapillomas of the skin, a tissue-specific phenotype analogous to that observed in natural bpv-1 infection of cattle. oncogenesis is slow, with tumours first arising at 8-9 months of age, usually in areas prone to wounding. extrachromosomal bpv-1 dna is detected in all tumours, whereas normal tissues show only integrated dna. | 1986 | 3018579 |
| characterization of fischer rat embryo (cref) cells transformed by bovine papillomavirus type 1. | transformation of an established fischer rat embryo (cref) cell line by bovine papillomavirus type 1 (bpv-1), in contrast to transformation by type 5 adenovirus or the t24 (ha-ras) oncogene, resulted in transformants which did not exhibit a major increase in saturation density or a decrease in 125i-epidermal growth factor binding. bpv-1-transformed cref clones did, however, grow in agar suspension culture and were tumorigenic in both nude mice and fischer rats. the majority of transformed clones ... | 1986 | 3019001 |
| differential regulation of papilloma virus early gene expression in transformed fibroblasts and carcinoma cell lines. | treatment of bovine papilloma virus (bpv) 1-transformed mouse fibroblasts with cycloheximide led to a 10-fold increase in the amount of viral transcripts, after as little as 1 h of protein synthesis inhibition. northern blots revealed no qualitative changes in the rna pattern. nuclear run-on experiments showed about a 7-fold increase in specific transcriptional activity after cycloheximide treatment. the half-life of bpv1 mrna was twice as long as in untreated controls. these results indicate th ... | 1986 | 3019673 |
| bovine papillomavirus type 1 3' early region transformation and plasmid maintenance functions. | we examined bovine papillomavirus type 1 (bpv-1) dnas mutated in the e2 open reading frame (orf) to determine their ability (i) to transform c127 cells and (ii) to remain extrachromosomal in transfected cells. results obtained with deletion mutants and insertion mutants containing a linker with translational termination codons in all possible reading frames indicated that an e2 orf gene product(s) is necessary for efficient transformation, as well as viral plasmid replication and maintenance in ... | 1986 | 3021996 |
| a bovine papillomavirus type 1-encoded modulator function is dispensable for transient viral replication but is required for establishment of the stable plasmid state. | a bovine papillomavirus (bpv) type 1-encoded function (m) which is a negative regulator of viral plasmid replication has been described elsewhere (berg et al. cell, in press; roberts and weintraub, cell, in press). we report here that expression of m, which is a repressor of transient bpv replication and is not required as a positive factor in these assays, is required for the establishment of the viral genome as a stable nuclear plasmid. this function is encoded in part by the 5' portion of the ... | 1986 | 3022005 |
| complementation of a bovine papilloma virus low-copy-number mutant: evidence for a temporal requirement of the complementing gene. | we identified a bovine papilloma virus function encoded by the e6/e7 gene, which is required for both bpv high-copy-number replication and maintenance of transformation of cultured cells. a cdna copy of this gene was isolated and expressed from a retrovirus vector. we found that complete complementation of a bpv low-copy-number mutant (dl576) by the cdna encoding the e6/e7 gene was temporally dependent. when both the e6/e7 cdna and dl576 were introduced together into cells, wild-type replication ... | 1986 | 3022134 |
| efficient transcription of a caenorhabditis elegans heat shock gene pair in mouse fibroblasts is dependent on multiple promoter elements which can function bidirectionally. | a divergently transcribed pair of caenorhabditis elegans hsp16 genes was introduced into mouse fibroblasts by stable transfection with vectors containing bovine papillomavirus plasmid maintenance sequences and a selectable gene. the hsp16 genes were transcriptionally inactive in the mouse cells under normal growth conditions and were strongly induced by heat shock or arsenite. in a cell line with 12 copies of the gene pair, there were estimated to be more than 10,000 hsp16 transcripts in each ce ... | 1986 | 3023964 |
| glucocorticoid inhibition of transcription from episomal proopiomelanocortin gene promoter. | glucocorticoid hormones alter transcription of specific genes. glucocorticoid-stimulated genes have been especially useful in unraveling molecular events responsible for positive gene regulation in mammals. the gene encoding proopiomelanocortin (pomc), which is under feedback inhibition by glucocorticoids, provides a model system to study negative gene regulation. using an episomal bovine papilloma virus vector, we now demonstrate that a 769-base-pair fragment containing the rat pomc promoter is ... | 1986 | 3024155 |
| the noncoding region of hpv-6vc contains two distinct transcriptional enhancing elements. | hpv-6vc subgenomic fragments were inserted into an enhancer-dependent expression vector for chloramphenicol acetyltransferase (cat) and assayed for the presence of transcriptional enhancing elements. a transcriptional enhancing element was detected in the noncoding region (ncr) of the hpv-6vc viral genome when the cat assays were performed in viral transformed human kidney cell lines (293 and 324k), in human cervical carcinoma cell lines (hela and siha), and in bovine papillomavirus type 1 (bpv- ... | 1986 | 3024399 |
| the minute virus of mice p39 transcription unit can encode both capsid proteins. | the right-hand 80% of the genome of minute virus of mice (mvm) was cloned into the bovine papillomavirus type i shuttle vector and used to transfect mouse c127 cells. transformed lines were isolated that efficiently produce both authentic mvm capsid proteins at a ratio similar to that seen in a normal viral infection, and these proteins assemble into intact empty virions. the only transcription of mvm sequences detected in these lines was representative of the viral p39 transcription unit, which ... | 1986 | 3951017 |
| comparison of peroxidase-antiperoxidase and avidin-biotin complex methods for the detection of papillomavirus in histological sections of the cervix uteri. | a study was undertaken to determine the relative sensitivities of the peroxidase-antiperoxidase (pap) and avidin-biotin complex (abc) methods for the detection of human papillomavirus (hpv) antigens in acetic acid-ethanol fixed paraffin-embedded cervical tissue. tissue sections prepared from 14 women suspected to have hpv infections with either atypia or dysplasia were stained immunohistochemically using an antiserum against genus-specific (common) antigen of bovine papillomavirus. detection of ... | 1986 | 3029653 |
| cell cycle-dependent expression of a stable episomal human histone gene in a mouse cell. | we have constructed a recombinant plasmid that includes a cell cycle-dependent human h4 histone gene with 650 base pairs of 5' and 900 base pairs of 3' flanking sequences and the 69% transforming fragment of bovine papilloma virus. when transfected into c127 mouse cells, this plasmid is maintained as a stable episome with approximately 20 copies per cell. micrococcal nuclease digestion indicates that the episomal human histone gene is packaged as chromatin. the human h4 histone transcript is ini ... | 1986 | 3458197 |
| treatment of bovine-papillomavirus-type-1 (bpv)-transformed mouse cells with aromatic retinoid and retinoic acid. | 1985 | 3006607 | |
| papillomaviruses and their involvement in oncogenesis. | papillomaviruses have been identified as the causative agents of benign epithelial proliferation in many animals including man. recent evidence has shown that each viral type will only infect a specific species and tissue. furthermore, certain papillomavirus types have been found associated with lesions capable of malignant conversion, particularly in response to secondary physical or chemical factors. many advances have been made in identifying particular papillomavirus types inducing papilloma ... | 1985 | 3011141 |
| the bovine papillomavirus distal "enhancer" is not cis essential for transformation or for plasmid maintenance. | we constructed a mutant of bovine papillomavirus type 1 (bpv-1) dna that lacked a transcriptional enhancer located 3' to the polyadenylation site of the early viral rnas expressed in transformed cells. this mutant dna, when separated from the procaryotic sequences, transforms mouse cells with an efficiency comparable to that of the full bpv-1 genome, and it exists as a stable multicopy plasmid in transformed cells. the bpv-1 distal enhancer suppresses the effects of a cis-inhibitory element in p ... | 1985 | 3018516 |
| type 1 human t-cell leukemia virus small envelope protein expressed in mouse cells by using a bovine papilloma virus-derived shuttle vector. | in an attempt to express the small (transmembrane) envelope protein p21e of type 1 human t-cell leukemia (lymphotrophic) virus (htlv-1) exclusive of other viral gene products, we have constructed a recombinant plasmid clone (pmbe-1) in a bovine papillomavirus-derived mammalian expression vector. mouse c127 cells transfected with the pmbe-1 plasmid expressed the introduced htlv-1 viral gene(s) as demonstrated by northern blot and indirect immunofluorescence with natural human antisera. the transf ... | 1985 | 3018517 |
| enhancer-dependent expression of the rat preproinsulin gene in bovine papillomavirus type 1 vectors. | the effect of position in a bovine papillomavirus type 1 (bpv-1) vector on foreign gene expression was assessed with the rat preproinsulin (ri1) gene. the ri1 gene was inserted at each of the bpv-1/pml2d junctions in either transcriptional orientation in derivatives of the pdbpv-1(142-6) vector which consists of the bamhi linear genome of bpv-1 dna cloned into pml2d. transformed lines of c127 cells were established and assayed for ri1 gene expression. cells containing the ri1 gene at the 3' end ... | 1985 | 3018523 |
| nucleotide sequence of bovine papillomavirus type 2 late region. | the late region of bovine papillomavirus type 2 (bpv-2) dna has been identified. the complete nucleotide sequence of the region was determined and revealed two large open reading frames. the dna sequence results and the predicted amino acid sequence of putative polypeptides encoded by this region are presented. comparative analysis of the bpv-2 late region and the corresponding area of bpv-1 was performed. this study demonstrates that identical genetic organization and considerable nucleotide se ... | 1985 | 2981958 |
| genetic analysis of bovine papillomavirus type 1 trans-acting replication factors. | the establishment of bovine papillomavirus type 1 in somatic mammalian cells is mediated by extrachromosomal replication and stable maintenance of the viral genome as a multicopy nuclear plasmid. previous studies indicated the requirement of viral gene expression for bovine papillomavirus type 1 replication and plasmid maintenance (m. lusky and m. r. botchan, cell 36:391-401, 1984; turek et al., proc. natl. acad. sci. u.s.a. 79:7914-7918, 1982). to define the viral genes which are necessary for ... | 1985 | 2983102 |
| bovine papillomavirus contains multiple transforming genes. | bovine papillomavirus type 1 (bpv-1) and its cloned full-length dna can transform rodent cells in vitro, and the viral dna persists as an extrachromosomal multicopy plasmid in these transformed cells. previous studies have identified at least five discrete viral rnas that are expressed in bpv-1 transformed cells and have shown that these transcripts share a 3' coterminus. to further define the structure of these rnas and to characterize the functions of individual viral transcripts, we construct ... | 1985 | 2983327 |
| the biology of papillomaviruses and their role in oncogenesis. | a large number of different papillomavirus types have been identified. several viruses often infect the same species and each virus is associated with a defined tissue. recent evidence has shown that certain benign lesions can undergo malignant transformation in both animals and humans in response to genetic or environmental factors. fine mapping of the structure and function of the viral genome may enhance our understanding of the interaction between the virus and the cofactors involved in mali ... | 1985 | 2986520 |
| transformation of cultured equine fibroblasts with a bovine papillomavirus. | fetal equine fibroblasts exposed to bovine papillomavirus became transformed by the criteria of morphological alterations and the acquisition of an increased life span, although they failed to grow in soft agar. papillomavirus genome persisted in the transformed fibroblasts and was apparently not integrated with the cellular genome. these findings support the notion that bovine papillomaviruses are involved in the production of equine sarcoids. | 1985 | 2988095 |
| messenger rnas from the transforming region of bovine papilloma virus type i. | messenger rnas present in c127 mouse cells transformed by bovine papilloma virus type 1 (bpv-1) were studied by the s1 nuclease protection technique, northern blotting, and electron microscopic heteroduplex analysis. the results revealed at least five classes of spliced mrnas which we designate types 1 to 5. they had a common poly(a) addition site located at co-ordinate 53 and all mrnas, except the type 3 mrnas, contained an exon located between co-ordinates 41 and 53. in the type 1 mrnas this e ... | 1985 | 2989533 |
| bovine papillomavirus type 1 monoclonal antibodies. | bovine papillomavirus type 1 (bpv-1) and type 2 (bpv-2) are the etiologic agents of fibropapillomas in cattle. polyclonal antisera produced against bpv-1 structural antigens are cross-reactive with bpv-2. in this study bpv-1 type-specific monoclonal antibodies were produced that were not reactive with bpv-2. these monoclonal antibodies could be used for identification of bpv-1 structural antigens in acetone-fixed, frozen sections by immunofluorescence and formalin-fixed, paraffin-embedded sectio ... | 1985 | 2989600 |
| expression of a functional influenza viral cap-recognizing protein by using a bovine papilloma virus vector. | the gene for the influenza viral pb2 protein, which recognizes and binds the 5'-terminal cap 1 structures (m7gpppnm) on eukaryotic mrnas, was inserted into a bovine papilloma virus vector under the control of a mouse metallothionein i (mt-i) promoter. after transfection of this vector into mouse nih 3t3 cells, a cell line, cpb2, was obtained that produces pb2-specific mrna and authentic pb2 protein. induction of the mt-i promoter with cdcl2 causes about a 10-fold increase in pb2 mrna and protein ... | 1985 | 2989815 |
| transactivation of a bovine papilloma virus transcriptional regulatory element by the e2 gene product. | we have mapped a transcriptional regulatory sequence within the 1.0 kb noncoding region of the bovine papilloma virus (bpv-1) genome, using an enhancer dependent expression vector for chloramphenicol acetyltransferase. this transcriptional regulatory element works independently of position and orientation, and its function is significantly augmented in bpv-1 transformed c127 cells and in monkey cv-1 cells acutely transfected with plasmids expressing bpv-1 early gene products. using defined delet ... | 1985 | 2990724 |
| lines of bpv-transformed murine cells that constitutively express influenza virus hemagglutinin. | we have developed and characterized several murine cell lines that constitutively express either the full-length, membrane-bound form of influenza virus hemagglutinin (ha) or a truncated version of the protein (hasec) that lacks the carboxyterminal anchoring sequences and is secreted from cells. cdnas encoding ha or hasec were linked to the murine metallothionein-i promoter or the sv40 early promoter, and inserted into plasmids containing the transforming dna fragment of bovine papilloma virus ( ... | 1985 | 2990897 |
| the presence of bovine papillomavirus type 4 dna is not required for the progression to, or the maintenance of, the malignant state in cancers of the alimentary canal in cattle. | in the western highlands of scotland there is a very high incidence of alimentary cancers in cattle. the carcinomas of the upper alimentary canal are found in association with virus-induced benign papillomas, and transformation of papillomas to carcinomas has been observed. strong circumstantial evidence suggests that the progression to malignancy is due to the interplay between the virus, bovine papillomavirus type 4 (bpv-4), and carcinogen(s) present in bracken fern, which infests the marginal ... | 1985 | 2992946 |
| molecular cloning and nucleotide sequence of deer papillomavirus. | the genome of deer papillomavirus (dpv) isolated from american white-tailed deer was cloned into pbr322, and the entire nucleotide sequence of 8,374 base pairs was determined. the overall genetic organization of the dpv genome was similar to that of other papillomaviruses. all significant open reading frames were located on one strand, and the locations of putative promoters and polyadenylation signals were similar to those identified in the closely related bovine papillomavirus type 1 (bpv-1) g ... | 1985 | 2993669 |
| high spontaneous mutation frequency of bpv shuttle vector. | a recombinant shuttle vector containing the entire bovine papillomavirus (bpv) genome, sequences from pbr322, and the escherichia coli gpt gene was used to transform mouse c127 cells. plasmid extracted from the transformed mouse cells was used to transform a gpt- derivative of e. coli hb101, and the relative frequency of plasmids carrying a mutation in the gpt gene was determined. approximate mutant frequencies of 3-16 x 10(-3) were observed for plasmid molecules which had been passaged through ... | 1985 | 2994240 |
| enzyme-linked immunosorbent assay for the detection of bovine papillomavirus. | an enzyme-linked immunosorbent assay has been developed to detect and quantitate bovine papillomavirus in partially purified and in purified viral preparations, using rabbit antiserum against group-specific papillomavirus structural antigens and alkaline phosphatase-labeled affinity purified goat antibody to rabbit immunoglobulin g. viral detection correlated well with negative-stain electron microscopy of the various preparations and peroxidase-antiperoxidase staining of paraffin sections of th ... | 1985 | 2994527 |
| identification of the protein encoded by the e6 transforming gene of bovine papillomavirus. | papillomaviruses (pv) contain several conserved genes that may encode nonstructural proteins; however, none of these predicted gene products have been identified. papillomavirus e6 genes are retained and expressed as rna in pv-associated human and animal carcinomas and cell lines. this suggests that the e6 gene product may be important in the maintenance of the malignant phenotype. the e6 open reading frame of the bovine papillomavirus (bpv) genome has been identified as one of two bpv genes tha ... | 1985 | 2996134 |
| a cutaneous fibropapilloma from a red deer (cervus elaphus) associated with a papillomavirus. | a cutaneous fibropapilloma was found on a scottish red deer (cervus elaphus), and a papillomavirus was isolated from it. the virus appeared to be related to bovine papillomavirus type 1 (bpv1) or type 2 (bpv2) because: (i) it cross-reacted in peroxidase-antiperoxidase tests with antisera raised against these virions; (ii) bpv1 and bpv2 dnas cross-hybridized to the red deer papillomavirus in situ; and (iii) bpv1 and/or bpv2 dna cross-hybridized to the red deer papillomavirus dna on southern blots ... | 1985 | 2997076 |
| amplification of a bovine papillomavirus-simian virus 40 chimera. | a chimeric plasmid, pbop, containing bovine papillomavirus (bpv) and the origin of replication from simian virus 40 (sv40) was constructed. the plasmid was established in mouse cells, where it was maintained stably as an autonomous bpv replicon. lines carrying pbop were fused to cells of cos-7, a simian line producing sv40 t antigen. replication dependent on the sv40 origin and having the kinetics and approximate amplitude of an sv40 infection ensued. sv40 replication is therefore dominant over ... | 1985 | 2997482 |
| z-dna: still searching for a function. | 1985 | 2997919 | |
| sequence homologies between bovine papillomavirus genomes mapped by a novel low-stringency heteroduplex method. | the bovine papillomaviruses (bpvs) types 1, 2, and 5 cause fibropapillomas whereas bpvs types 3, 4, and 6 cause true papillomas. a novel method of heteroduplex mapping at low stringency of hybridisation has identified the position and relative orientation of distantly related sequences in the genomes of these viruses. the genomes of bpv-1 and bpv-2 are closely related but both show a high degree of sequence divergence from the bpv-5 genome. a 1.25-kb sequence adjacent to the unique bamhi site of ... | 1985 | 2998027 |