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1.
J Invest Dermatol ; 91(1): 43-8, 1988 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-2838553

RESUMO

A new human papillomavirus (HPV) was discovered in disseminated, macular, pityriasis versicolor-like lesions on the skin of the neck, face, scalp, and pubic region of a 42-year-old male suffering from Hodgkin's disease. Histopathology revealed features characteristic of epidermodysplasia verruciformis (ev). In contrast to classical ev, the lesions were almost exclusively seen in previously irradiated and UV-exposed skin areas. Papillomavirus capsid antigen was demonstrated with the genus-specific antiserum and the patient's serum, which had IgM and IgG antibody titers. HPV DNA was isolated from biopsies and cloned into the vector pIC20H. It proved to be related to ev-associated viruses, showing 23% cross-hybridization with DNA of the closest relative HPV14. The new HPV type was named HPV46. The genome was physically mapped and colinearly aligned with HPV8 DNA to establish its gene organization. Interferon treatment of the patient did not significantly change the clinical picture nor was the concentration of viral DNA per lesion affected. However, no virus capsid antigen was detectable after starting treatment.


Assuntos
Epidermodisplasia Verruciforme/complicações , Doença de Hodgkin/complicações , Interferon Tipo I/uso terapêutico , Papillomaviridae/classificação , Adulto , Clonagem Molecular , DNA Viral/análise , Epidermodisplasia Verruciforme/tratamento farmacológico , Epidermodisplasia Verruciforme/patologia , Genes Virais , Humanos , Masculino , Hibridização de Ácido Nucleico , Papillomaviridae/genética , Proteínas Recombinantes
2.
J Invest Dermatol ; 113(1): 122-6, 1999 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-10417630

RESUMO

Epidermodysplasia verruciformis-associated human papillomaviruses and in particular human papillomavirus type 5 were recently shown to be highly prevalent in psoriatic skin. We have analyzed lesional skin from 54 psoriasis patients for infections with genital-specific and epidermodysplasia verruciformis-specific human papillomaviruses to define the spectrum of involved human papillomavirus types and to test if it is influenced by psoralen ultraviolet A therapy. Using polymerase chain reaction analysis we could detect human papillomavirus sequences in skin lesions of 83% of the tested patients. In contrast, human papillomavirus-DNA was only demonstrated in 19% of skin samples from 42 dermatologically healthy, immunocompetent individuals. Sequence analysis of the polymerase chain reaction amplimers revealed 14 human papillomavirus types, all belonging to the epidermodysplasia verruciformis or epidermodysplasia verruciformis-related papillomaviruses. Only in one case we identified sequences related to those of genital viruses, which, however, represented a putatively new human papillomavirus type. The most prevalent human papillomavirus type in our patient series was human papillomavirus type 36, found in 62% of the patients positive for human papillomavirus-DNA, followed by human papillomavirus type 5 (38%) and human papillomavirus type 38 (24%). Multiple infections with two to five different human papillomavirus types could be detected in skin samples of 63% of the analyzed patients. The overall human papillomavirus detection rate did not differ significantly between patients which have been subjected to psoralen ultraviolet A photochemotherapy or solely treated with topical preparations (77 vs 89%). Human papillomavirus type 5, however, could be detected significantly more frequent in lesions of psoralen ultraviolet A-treated patients (p < 0.001). Our data strongly argue for infections with epidermodysplasia verruciformis-specific papillomaviruses being an almost consistent feature of the lesional psoriatic skin and substantiate the importance of further studies to elucidate a possible involvement of human papillomaviruses in psoriasis pathology.


Assuntos
Terapia PUVA , Papillomaviridae , Infecções por Papillomavirus/tratamento farmacológico , Psoríase/tratamento farmacológico , Infecções Tumorais por Vírus/tratamento farmacológico , Adolescente , Adulto , Idoso , Sequência de Aminoácidos , Sequência de Bases , Biópsia , DNA Viral/genética , Epidermodisplasia Verruciforme/virologia , Humanos , Pessoa de Meia-Idade , Dados de Sequência Molecular , Papillomaviridae/classificação , Papillomaviridae/genética , Prevalência , Psoríase/epidemiologia , Psoríase/virologia , Alinhamento de Sequência , Análise de Sequência de DNA , Homologia de Sequência de Aminoácidos , Homologia de Sequência do Ácido Nucleico , Pele/patologia , Pele/virologia , Dermatopatias Virais/tratamento farmacológico , Dermatopatias Virais/patologia
3.
J Invest Dermatol ; 115(1): 124-8, 2000 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-10886519

RESUMO

DNA of human papillomaviruses has frequently been detected in nonmelanoma skin cancers, raising the question of a possible causal contribution of these tumor viruses to skin carcinogenesis. Basal cell carcinomas are the most common nonmelanoma skin cancers; however, so far they are only poorly analyzed with regard to human papillomavirus infection. We searched for human papillomavirus-DNA in 69 biopsies from 61 immunocompetent basal cell carcinoma patients from two geographic locations in Europe using six different polymerase chain reaction primer systems. We could demonstrate human papillomavirus-DNA in 43.5% of the tested tumors. Human papillomavirus positivity did not seem to correlate with the duration of disease or patients' age. The vast majority of virus types in the biopsies belonged to the group of epidermodysplasia verruciformis-associated human papillomavirus. Of 31 sample pairs tested for human papillomavirus-DNA in tumors as well as in perilesional healthy skin, seven carried viral sequences in lesional and healthy skin and three only in the basal cell carcinoma. Six of the seven human papillomavirus-positive basal cell carcinoma/healthy skin pairs contained identical human papillomavirus types in tumors and histologically normal tissue. Forty basal cell carcinoma patients were additionally analyzed for IgG antibodies against virus-like particles of three representative epidermodysplasia verruciformis-human papillomavirus types: 8, 15, and 36. No statistically significant differences could be detected between human papillomavirus antibody prevalences of basal cell carcinoma patients and of dermatologically healthy individuals. Moreover, serologic findings did not correlate with the detection of specific human papillomavirus types in tumors. Our results seem to suggest that the occurrence of human papillomavirus-DNA in basal cell carcinoma does not reflect a major etiologic role of human papillomavirus in this cancer.


Assuntos
Carcinoma Basocelular/genética , DNA Viral/análise , Papillomaviridae/genética , Neoplasias Cutâneas/genética , Idoso , Idoso de 80 Anos ou mais , Anticorpos Antivirais/sangue , Biópsia , Carcinoma Basocelular/patologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Papillomaviridae/imunologia , Neoplasias Cutâneas/patologia
4.
J Invest Dermatol ; 111(4): 696-701, 1998 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-9764856

RESUMO

There is increasing evidence for widespread occurrences of infection with Epidermodysplasia verruciformis-related human papillomaviruses, both in the general population and in immunosuppressed patients. In order to test for the prevalence of antibodies directed against the native L1 epitopes exposed on the surface of the virions, we have established an IgG-specific enzyme-linked immunosorbent assay with L1 virus-like particles of the Epidermodysplasia verruciformis-specific human papillomavirus 8 as antigen to screen 567 representative serum samples from the general population and immunosuppressed/dermatologic patients. Among healthy European donors (n = 210), 7.6% were found to be seropositive. In a group of renal transplant recipients (n = 185) the antibody prevalence was elevated to 21.1%, irrespective of the presence or absence of skin cancer. High positivity rates could be detected among (i) immunocompetent patients with nonmelanoma skin tumors (45.6%, n = 79) and (ii) Psoralene/UVA treated psoriasis patients (42.9%, n = 42). In contrast, anti-human papillomavirus 8-virus-like particle antibodies were found in only 6.8% of Hodgkin lymphoma patients (n = 44).


Assuntos
Epidermodisplasia Verruciforme/virologia , Papillomaviridae , Infecções por Papillomavirus/imunologia , Neoplasias Cutâneas/etiologia , Infecções Tumorais por Vírus/imunologia , Anticorpos Antivirais/análise , Ensaio de Imunoadsorção Enzimática , Humanos , Tolerância Imunológica , Imunocompetência , Transplante de Rim/imunologia , Proteínas Oncogênicas Virais/química , Proteínas Oncogênicas Virais/isolamento & purificação , Papillomaviridae/imunologia , Prevalência , Fatores de Risco , Neoplasias Cutâneas/epidemiologia , Neoplasias Cutâneas/imunologia
5.
Dermatol Clin ; 9(2): 267-76, 1991 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-1647905

RESUMO

A variety of HPV types infect the anogenital mucosa, giving rise to lesions that differ in clinical appearance, histology, and risk of malignant progression. Human papillomavirus type 16 is distinguished by a strong association with high-grade intraepithelial neoplasia and the greatest prevalence in anogenital malignancy. Most cancers appear to have a multifactorial cause, and HPV infection alone is probably insufficient for malignant transformation. The consistent association between HPV infection and anogenital cancers emphasizes that the papillomaviruses may have a necessary role in carcinogenesis, however. Hence, there is a prospect that vaccination programs may one day allow public health control of HPV infection, thereby eliminating an important risk factor.


Assuntos
Neoplasias do Ânus/microbiologia , Neoplasias dos Genitais Femininos/microbiologia , Neoplasias dos Genitais Masculinos/microbiologia , Papillomaviridae , Infecções Tumorais por Vírus , Animais , Neoplasias do Ânus/patologia , Neoplasias do Ânus/prevenção & controle , Condiloma Acuminado/microbiologia , Condiloma Acuminado/patologia , Feminino , Neoplasias dos Genitais Femininos/patologia , Neoplasias dos Genitais Femininos/prevenção & controle , Neoplasias dos Genitais Masculinos/patologia , Neoplasias dos Genitais Masculinos/prevenção & controle , Humanos , Masculino , Infecções Tumorais por Vírus/patologia , Infecções Tumorais por Vírus/prevenção & controle , Vacinação
8.
Intervirology ; 22(3): 177-80, 1984.
Artigo em Inglês | MEDLINE | ID: mdl-6094390

RESUMO

Human papillomavirus (HPV) DNA was isolated from a clinically diagnosed flat wart and proved to be related to HPV2. The isolate showed 55% cross-hybridization with HPV2a. A physical map of restriction enzyme cleavage sites differed completely from those of HPV2a and HPV2b. The new HPV2 subtype, which will be classified as HPV2c, was found to be very prevalent in common warts.


Assuntos
DNA Viral/genética , Papillomaviridae/genética , Clonagem Molecular , Enzimas de Restrição do DNA , Humanos , Verrugas/microbiologia
9.
J Bacteriol ; 136(1): 295-303, 1978 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-30748

RESUMO

Trypsin and other proteolytic enzymes, added together with transforming DNA or during cell-DNA contact to competent cultures of several streptococcal strains, enchanced (10 to 600%) the yield of genetic transformation (stimulation). With few exceptions, the level of stimulation was high (over 100%) when competence was low (below 2%). Stimulation was caused by the action of an enzyme on competent cells and not on any other component of transformation mixture. The phenomenon occurred when the enzyme was added to the culture not earlier than 7 min before and not later than 5 min after the period of cell-DNA contact. The presence of trypsin during cell-DNA contact caused: (i) the alterations at cell surface, demonstrated by electron microscopy, increased release of 3H-amino acid-labeled material, and higher cell susceptibility to autolysis; (ii) the increase of both total and irreversible binding of DNA by the cells; and (iii) the decrease of early nucleolytic degradation of DNA by cells. These and other data point to the importance of a delicate balance of recipient cell's surface nuclease activities in the effectiveness of transformation process. It is also possible that trypsin eliminates an unknown cellular factor which obstructs DNA-cell receptors interaction.


Assuntos
Peptídeo Hidrolases/farmacologia , Streptococcus pneumoniae/genética , Streptococcus sanguis/genética , Tripsina/farmacologia , DNA Bacteriano/metabolismo , Endonucleases/metabolismo , Estimulação Química , Streptococcus pneumoniae/efeitos dos fármacos , Streptococcus sanguis/efeitos dos fármacos , Transformação Bacteriana/efeitos dos fármacos
10.
Int J Cancer ; 43(1): 41-4, 1989 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-2536006

RESUMO

Human papillomavirus (HPV) 16 is most prevalent in cervical cancers and also persists in metastases. We examined HPV16-DNA-positive primary cancers and several lymph nodes from each of 14 patients to evaluate the use of HPV16 DNA as a diagnostic marker for the detection of early node involvement. The HPV16 DNA was exclusively integrated in 39% of the primary cancers, predominantly episomal in 36%, and integrated and extrachromosomal to a similar extent in 25%. Thirteen of 16 involved lymph nodes contained HPV16 sequences. Integrated viral DNA showed the same pattern in primary tumors and in metastases. The level of extrachromosomal HPV16 DNA, however, appeared to be considerably reduced in some nodes. HPV16 DNA was also detected in 18 out of 59 histologically negative lymph nodes. This result recommends nucleic acid hybridization as a sensitive method for the detection of HPV-DNA-positive cancer cells. The prognostic significance of viral sequences in histologically negative nodes remains to be established.


Assuntos
Biomarcadores Tumorais/análise , DNA Viral/análise , Linfonodos/microbiologia , Neoplasias do Colo do Útero/microbiologia , Southern Blotting , Feminino , Humanos , Metástase Linfática , Papillomaviridae/genética
11.
J Virol ; 58(2): 626-34, 1986 May.
Artigo em Inglês | MEDLINE | ID: mdl-3009874

RESUMO

Human papillomavirus (HPV) 8 induces skin tumors which are at high risk for malignant conversion. The nucleotide sequence of HPV8 has been determined and compared to sequences of papillomaviruses with different oncogenic potential. The general organization of the HPV8 genome is similar to that of other types. Highly conserved, genus-specific sequences were found in open reading frames (ORFs) E1, E2, and L1. In ORFs E6, E7, and L2, HPV8 is more distantly related, but it was possible to differentiate subgenera in which HPV8 belonged to the HPV1-cottontail rabbit papillomavirus group. Sequences within ORF E4 and part of ORF L2 are rather type specific. HPV8 stands out by several unique features: the considerably reduced size of the noncoding region (397 base pairs), with a seemingly low potential for forming complex secondary structures; a cluster of putative promoter elements in the 3' half of ORF E1; an RNA polymerase III promoter-like sequence close to the C terminus of ORF E2; and of particular interest, the homology between the putative protein encoded by ORF E4 and the Epstein-Barr virus nuclear antigen 2 protein, which may reflect similar mechanisms in virus-mediated transformation.


Assuntos
DNA Viral/genética , Genes Virais , Papillomaviridae/genética , Infecções Tumorais por Vírus/microbiologia , Verrugas/microbiologia , Sequência de Aminoácidos , Antígenos Virais/genética , Sequência de Bases , Antígenos Nucleares do Vírus Epstein-Barr , Herpesvirus Humano 4/genética , Humanos , Lesões Pré-Cancerosas/microbiologia , Regiões Promotoras Genéticas , Processamento Pós-Transcricional do RNA , Splicing de RNA , RNA Viral/genética , Homologia de Sequência do Ácido Nucleico , Neoplasias Cutâneas/etiologia , Especificidade da Espécie , Proteínas Virais/genética
12.
Virology ; 196(2): 674-81, 1993 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-8396805

RESUMO

Human papillomavirus (HPV) 8 belongs to the HPV types frequently associated with skin cancers of Epidermodysplasia verruciformis (EV)-patients. There are 33 nucleotides (M33 motif) in the 5'-part of the non-coding regulatory region of HPV8, which appear highly conserved among EV-specific HPVs and are consistently followed by an AP1 binding site. These sequences were shown to constitute an essential activator of transcription driven by the HPV8 late promoter P7535. The M33/AP1 element displayed properties of a constitutive enhancer, being also able to stimulate the activity of the heterologous thymidine kinase promoter in a position-independent manner. No protein binding could be detected within the 5'-part of the M33/AP1 region, which contributed significantly to the overall activity of the HPV8 enhancer. As shown by DNasel-footprinting, the central and the 3'-part of the enhancer region were involved in interactions with nuclear proteins. Three specific complexes could be observed in gel retardation tests with nuclear extracts from epithelial cells. One of these interactions involved the AP1 protein. Analysis of deletion and point mutations revealed binding of the AP1 protein to be essential for transcriptional activation, but DNA-protein interactions within M33 were important for maximal stimulation. The response to the phorbol ester TPA also required a cooperation of M33 and AP1.


Assuntos
Epidermodisplasia Verruciforme/microbiologia , Regulação Viral da Expressão Gênica , Papillomaviridae/genética , Sequências Reguladoras de Ácido Nucleico/genética , Transcrição Gênica , Sequência de Bases , Cloranfenicol O-Acetiltransferase/biossíntese , Cloranfenicol O-Acetiltransferase/genética , Análise Mutacional de DNA , Humanos , Dados de Sequência Molecular , Ésteres de Forbol/farmacologia , Mutação Puntual , Proteínas Recombinantes de Fusão/biossíntese , Deleção de Sequência , Fator de Transcrição Sp1 , Timidina Quinase/genética , Transcrição Gênica/efeitos dos fármacos , Células Tumorais Cultivadas
13.
J Virol ; 66(6): 3485-93, 1992 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-1316464

RESUMO

Human papillomavirus type 8 (HPV8) belongs to the HPV types associated with skin carcinomas of patients with epidermodysplasia verruciformis (EV). Its noncoding regulatory sequences (NCR) were shown to drive the expression of the reporter gene chloramphenicol acetyltransferase (cat) in transient assays with human epithelial cells (HT3 cells). This constitutive activity could be enhanced by coexpression of the HPV8 transactivator protein E2. The analysis of 5' deletions of the NCR showed that the EV-specific sequence motif M33 and the neighboring AP1 site are essential for the promoter activity, whereas 44 nucleotides located immediately upstream of M33 are strongly inhibitory. The same effects were observed in simian virus 40-immortalized fetal keratinocytes (SV61 cells) and spontaneously immortalized skin keratinocytes (HaCaT cells). By using primer extension and RNase protection analyses two promoters could be identified within the HPV8 NCR. A nested set of weak signals, corresponding to start sites between positions 175 to 179, represented the previously described E6 promoter. The vast majority of transcripts was initiated at position 7535 and shown to undergo processing at an NCR-internal splice donor (positions 1 to 8). The promoter P7535 is similar to late promoters of other skin-associated papillomaviruses as far as localization, transcript structure, and sequence characteristics are concerned. To confirm that P7535-initiated transcripts proceed indeed to the L1 gene for the major capsid protein, viral mRNAs from an HPV8-induced lesion of a patient with EV were characterized by RNase protection and sequence analysis of polymerase chain reaction-amplified cDNAs. The NCR leader (positions 7535 to 4) appeared in two messages with three exons each. The third exon started with the second ATG codon of L1 in both cases; the short central exons from the 3' part of the early coding region were defined by a common splice acceptor site (position 3303) and different splice donor sites (positions 3443 and 3704).


Assuntos
Regulação Viral da Expressão Gênica , Papillomaviridae/genética , Regiões Promotoras Genéticas/genética , Transcrição Gênica , Infecções Tumorais por Vírus/genética , Adulto , Sequência de Bases , Cloranfenicol O-Acetiltransferase/biossíntese , Análise Mutacional de DNA , Epidermodisplasia Verruciforme/microbiologia , Feminino , Humanos , Dados de Sequência Molecular , Proteínas Oncogênicas Virais/metabolismo , Precursores de RNA/genética , Splicing de RNA , Neoplasias Cutâneas/microbiologia
14.
Int J Cancer ; 41(1): 41-5, 1988 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-2826346

RESUMO

Colposcopically directed cervical punch biopsies from 362 patients were screened by Southern blot hybridization for the presence of DNA of human papillomavirus (HPV) 6, 10, 11, 16, 18, 31 and 33. The biopsies represented original squamous epithelium, epithelium of metaplastic origin, different stages of cervical intraepithelial neoplasia (CIN) and invasive carcinomas. HPV6/11, 16, 18 and 31 were detected in 2.9% to 13.7% of histologically normal epithelia. HPV6/11 prevailed in CIN I. HPV16 was clearly more abundant than other HPV types in high-grade CIN and invasive cancers (50%-60%), compared with healthy epithelium. Restriction enzyme cleavage analysis of DNA from primary cancers and corresponding metastases proved the stable association of HPV16 DNA with invasive tumor cells. Preliminary follow-up studies of CIN II patients suggested that HPV16-associated lesions are relatively more likely to persist or to progress. Taken together, the data support the notion of a higher oncogenic potential of HPV16.


Assuntos
Colo do Útero/microbiologia , DNA Viral/isolamento & purificação , Papillomaviridae/isolamento & purificação , Lesões Pré-Cancerosas/microbiologia , Displasia do Colo do Útero/microbiologia , Neoplasias do Colo do Útero/microbiologia , Colo do Útero/citologia , Colo do Útero/patologia , Células Epiteliais , Epitélio/microbiologia , Feminino , Humanos , Metaplasia , Papillomaviridae/genética , Lesões Pré-Cancerosas/patologia , Displasia do Colo do Útero/patologia , Neoplasias do Colo do Útero/patologia
15.
Acta Microbiol Pol ; 27(3): 181-91, 1978.
Artigo em Inglês | MEDLINE | ID: mdl-81592

RESUMO

The ablity of competent and noncompetent Streptococcus sanguis (strain Wicky) cells to release enzymes to the environment was studied. Both competent and noncompetent cells leaked the enzymes tested (aldolase, phosphatase and deoxyribonuclease), but the activities liberated from the competent cells were always roughly 2-fold higher than those released from noncompetent cells. This increased enzyme leakage from competent cells occured in all kinds of media and procedures employed. The leakage of enzymes followed a time-dependent kinetics (different for aldolase and phosphatase), was temperature sensitive and had a pH optimum. The increased enzyme release was most likely not due to cell disruption, but seemed to be rather a consequence of alteration in cell barrier permeability. These results strongly support the "unmasking" model proposed for explanation of competence development in bacteria.


Assuntos
Desoxirribonucleases/metabolismo , Frutose-Bifosfato Aldolase/metabolismo , Monoéster Fosfórico Hidrolases/metabolismo , Streptococcus sanguis/genética , Transformação Bacteriana , Concentração de Íons de Hidrogênio , Streptococcus sanguis/enzimologia , Temperatura
16.
J Virol ; 53(1): 13-8, 1985 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-2981331

RESUMO

Herpesvirus aotus type 2, a virus commonly found in owl monkeys without overt disease, has a similar genome structure to the oncogenic herpesviruses of nonhuman primates (herpesvirus saimiri, herpesvirus ateles). Virion DNA of herpesvirus aotus type 2 (M-DNA) has an unique 110-kilobase-pair region of low G + C content (40.2%, L-DNA), inserted between stretches of repetitive H-DNA (68.7% G + C, about 41 kilobase pairs per molecule) that are variable in length. A minority of virions contain defective genomes that consist of repetitive H-DNA only. The H-DNA is composed of various types of repeat units that are related in sequence with each other. The two dominant types of repeats (2.3 and 2.7 kilobase pairs) were cloned and compared by restriction enzyme cleavages and partial nucleotide sequencing. They are homologous in at least 1.3 kilobase pairs. The two forms of repeat units are randomly arranged and oriented in tandem. Reassociation kinetics did not allow detection of sequence homologies between H- and L-DNA of herpesvirus aotus type 2 and the respective sequences of oncogenic primate herpesviruses.


Assuntos
Genes Virais , Herpesviridae/genética , Simplexvirus/genética , Animais , Aotus trivirgatus , Sequência de Bases , Linhagem Celular , Clonagem Molecular , Enzimas de Restrição do DNA , DNA Viral/isolamento & purificação , Herpesvirus Saimiriíneo 2/genética , Rim , Cinética , Hibridização de Ácido Nucleico , Renaturação de Ácido Nucleico , Sequências Repetitivas de Ácido Nucleico , Especificidade da Espécie , Vírion/genética
17.
J Gen Virol ; 72 ( Pt 12): 2989-97, 1991 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-1662691

RESUMO

The non-coding region (NCR) of the epidermodysplasia verruciformis (EV)-associated human papillomavirus 8 (HPV-8) has been investigated for sequence-specific DNA-protein interactions with nuclear proteins from epithelial HeLa cells. Using DNase I protection analysis 18 footprints could be found within the HPV-8 NCR, covering altogether over 60% of both DNA strands. Several footprints coincided with the known binding sites of transcription factors (NF1, AP1, octamer and PEA3 consensus sequences); the other displayed no obvious similarities in this regard. The overall distribution of sequences involved in DNA-protein interactions differed clearly from the binding patterns reported for other HPVs. Parts of the two binding sites for the viral trans-activator protein E2 were shown to interact with non-E2 factors. The EV-specific NCR motifs M33, M29 and A/T box were all involved in protein binding. By comparing the footprints within the respective motifs of the closely related types HPV-8 and -19, quantitative and qualitative differences were detected for M33 and the A/T box.


Assuntos
DNA Viral/metabolismo , Proteínas de Ligação a DNA/metabolismo , Epidermodisplasia Verruciforme/microbiologia , Papillomaviridae/genética , Sequência de Bases , Sítios de Ligação , Impressões Digitais de DNA , Proteínas de Ligação a DNA/genética , Genes Virais , Células HeLa , Humanos , Dados de Sequência Molecular
18.
J Bacteriol ; 124(3): 1621-3, 1975 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-172490

RESUMO

Glucosylated deoxyribonucleic acid (DNA) from phages T4 and T6 competes poorly with homologous DNA causing only a slight decrease of transformation in Group H Streptococcus strain Challis. Other types of heterologous DNAs (Micrococcus luteus, Clostridium perfringens, Escherichia coli, calf thymus and non-glucosylated phage T6 DNA), in contrast to glucosylated T4 and T6 DNAs, compete with transforming DNA to the normal, high extent. These results indicate that as in transformation of Bacillus subtilis, the presence of glucose attached to 5-hydroxymethylcytosine in phage T6 DNA considerably decreases the interaction of such DNA with competent cells of the Challis strain. It also indicates that the guanine plus cytosine content of DNA is not decisive in determining its interaction with competent cells.


Assuntos
DNA Bacteriano , DNA Viral , DNA , Streptococcus , Transformação Genética , Animais , Bovinos , Clostridium perfringens , Colífagos , DNA/análise , DNA/metabolismo , DNA Bacteriano/análise , DNA Bacteriano/metabolismo , DNA Viral/análise , DNA Viral/metabolismo , Resistência Microbiana a Medicamentos , Escherichia coli , Glucose/análise , Micrococcus , Mutação , Especificidade da Espécie , Streptococcus/efeitos dos fármacos , Streptococcus/metabolismo , Estreptomicina/farmacologia , Timo
19.
J Virol ; 68(6): 3612-9, 1994 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-8189499

RESUMO

The noncoding region of the highly oncogenic, epidermodysplasia verruciformis-associated human papillomavirus type 8 contains a negative regulatory element (NRE). Quantitative RNase protection analysis confirmed that the NRE sequence acts as a silencer of transcription. A 38-bp sequence upstream of late promoter P7535 down-regulated expression from the homologous P7535 promoter, as well as the heterologous tk gene promoter, independently of its orientation relative to the test promoters. It also reduced gene expression when cloned downstream of the transcription units. Transient expression assays with keratinocytes and fibroblasts of epidermodysplasia verruciformis patients and controls demonstrated that the NRE activity is not cell specific. Gel retardation tests suggested that NRE specifically interacts with only one nuclear factor. Mutational analysis identified three NRE mutants which no longer formed a detectable DNA-protein complex but still repressed transcription, indicating that protein-DNA interaction is not relevant for the silencer function. The NRE contains a binding site of viral trans activator protein E2. It was shown that expression of E2 overrides the inhibitory effect of the NRE sequences. Binding of E2 and that of the cellular factor were mutually exclusive. The bifunctional nature of NRE acting as a silencer and a target site for viral trans activator E2 offers an interesting opportunity to regulate the switch from early to late transcription in the human papillomavirus life cycle.


Assuntos
Genes Virais , Papillomaviridae/genética , Regiões Promotoras Genéticas , Sequência de Bases , Células Cultivadas , DNA Viral/genética , DNA Viral/metabolismo , Epidermodisplasia Verruciforme/virologia , Regulação Viral da Expressão Gênica , Genes Reguladores , Humanos , Dados de Sequência Molecular , Mutagênese Sítio-Dirigida , Proteínas Nucleares/metabolismo , Proteínas Oncogênicas Virais/genética , Proteínas Oncogênicas Virais/metabolismo , Papillomaviridae/classificação , Papillomaviridae/metabolismo , Ligação Proteica , Transativadores/genética , Transativadores/metabolismo , Transcrição Gênica
20.
Graefes Arch Clin Exp Ophthalmol ; 223(3): 164-7, 1985.
Artigo em Inglês | MEDLINE | ID: mdl-2993107

RESUMO

A histologically proven conjunctival papilloma was examined for the presence of papillomavirus DNA by nucleic acid hybridization under relaxed conditions. It harbored papilloma-virus-specific DNA, which showed no detectable relationship with that of known virus types when tested under stringent conditions. This demonstrates that conjunctival papillomas are associated with more than one papillomavirus type. Viral diagnosis may turn out to be of prognostic value.


Assuntos
Neoplasias da Túnica Conjuntiva/análise , DNA Viral/análise , Papiloma/análise , Papillomaviridae/genética , Adulto , Biópsia , Neoplasias da Túnica Conjuntiva/patologia , Epitélio/patologia , Humanos , Masculino , Papiloma/patologia
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