Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: EC:3.1.30.2 (endonuclease)
 18,621 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

A virus (MnPV) with the structural characteristics of papilloma viruses was isolated from benign and malignant proliferations of adult animals of the inbred line 'GRA Giessen' of Mastomys natalensis. The particles can be banded in CsCl gradients at densities of 1.34 g/ml (full particles) and 1.29 g/ml (empty particles). The virus DNA has a buoyant density of 1.7104 g/ml and can exist in three different conformations (supercoiled circular, nicked circular and linear), the sedimentation values of which have been determined as 23 to 24S, 16 to 17S and 14 to 15S, respectively. Although the mol. wt. of MnPV DNA is similar to that of HPV 1 DNA, the size of the fragments obtained after cleavage of MnPV DNA with the restriction endonuclease Hae III is quite different from the pattern seen with human papilloma virus. The virion contains 12 different polypeptides; the major structural protein has a mol. wt. of 56 000. MnPV is shown to be the causative agent of the skin proliferations, because tumours can be induced by inoculation of purified virus, whereas no cutaneous alterations are observed when the particles are inoculated in the presence of anti-MnPV serum. MnPV can be re-isolated from the experimentally induced tumours.
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PMID:Mastomys natalensis papilloma virus (MnPV), the causative agent of epithelial proliferations: characterization of the virus particle. 21 19

Rapid advances have occurred in the characterization of human papilloma virus (HPV) types applying the new advanced techniques of restriction endonuclease analysis and molecular hybridization to human wart virus. Human papilloma virus can no longer be viewed as a single, homogeneous virus producing all varieties of clinical warts. At least three antigenically heterogeneous HPV types have been associated with common and plantar warts. Two additional HPV types have been found in patients with epidermodysplasia verruciformis. Condylomata acuminata and laryngeal papillomas contain viruses which are also distinct from the preceding viruses and may represent additional HPV types. This antigenic heterogeneity of HPV has important implications concerning the immunology of human warts which have not been taken into account in most previously published studies. Both antibody and cell-mediated responses may be seen in patients with active warts, but many patients with warts have no demonstrable immune reactions. The role of immunity in wart regression remains poorly understood. Nevertheless, the increased frequency of warts in patients receiving immunosuppressive drugs and with immune deficiency states and the immunologic alterations which occur in patients with regressing or cured warts compared to patients with active warts, particularly the increased frequency of cell-mediated responses and antibodies specific for viral antigens, support a possible role for immunity in the resolution of warts. The evidence to date, however, does not prove that immune mechanisms are directly responsible for the elimination of warts.
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PMID:Immunology of human warts. 22 34

By centrifuging total cellular DNA derived from human genital warts (condylomata acuminata) in CsCl-ethidium bromide gradients, supercoiled DNA was isolated. The molecular weight of this DNA was determined by agarose gel electrophoresis and amounted to 5.1 X 10(4). This DNA isolated from an individual genital wart was annealed to fractions of aqueous supernatants of the same wart after prior centrifugation of this material in CsCl density gradients. Annealing was observed at a density of approximately 1.32 g/ml corresponding to the expected density of papilloma virus particles. Since such particles were also observed in the same preparation by electron microscopy, it was concluded that the supercoiled DNA molecules were derived from papilloma virus nucleocapsids. Positive hybridization was found with six additional preparations from individual genital warts. Therefore, it seems that the isolated DNA prevails in condylomata acuminata. The DNA is different from the other five types of human papilloma viruses described thus far in regard to its restriction endonuclease cleavage patterns. The virus analyzed is tentatively designated as human papilloma virus type 6 (HPV 6).
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PMID:Partial characterization of viral DNA from human genital warts (Condylomata acuminata). 624 10

The complete DNA genomes of four distinct human papilloma viruses (human papilloma virus subtype 1a [HPV-1a], HPV-1b, HPV-2a, and HPV-4) were molecularly cloned in Escherichia coli, using the certified plasmid vector pBR322. The restriction endonuclease patterns of the cloned HPV-1a and HPV-1b DNAs were similar to those already published for uncloned DNAs. Physical maps were constructed for HPV-2a DNA and HPV-4 DNA, since these viral DNAs had not been previously mapped. By using the cloned DNAs, the genomes of HPV-1a, HPV-2a, and HPV-4 were analyzed for nucleotide sequence homology. Under standard hybridization conditions (Tm = --28 degrees C), no homology was detectable among the genomes of these papilloma viruses, in agreement with previous reports. However, under less stringent conditions (i.e., Tm = --50 degrees C), stable DNA hybrids could be detected between these viral DNAs, indicating homologous segments in the genomes with approximately 30% base mismatch. By using specific DNA fragments immobilized on nitrocellulose filters, these regions of homology were mapped. Hybridization experiments between radiolabeled bovine papilloma virus type 1 (BPV-1) DNA and the unlabeled HPV-1a, HPV-2a, or HPV-4 DNA restriction fragments under low-stringency conditions indicated that the regions of homology among the HPV DNAs are also conserved in the BPV-1 genome with approximately the same degree of base mismatch.
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PMID:Cloning of human papilloma virus genomic DNAs and analysis of homologous polynucleotide sequences. 625 65

To date over 60 different human papilloma virus (HPV) types have been described and novel HPV genomes are still being identified. The identification and taxonomy of papilloma viruses has become increasingly complex However, some types, especially HPV-16, -18 and to a lesser extent HPV-31 and -33, which are found in a high proportion of invasive cervical cancers and their metastases, are classified as high risk types For preventive reasons it is important to identify and classify the different HPV types in clinical specimens. Many of the methods used until recently are cumbersome. In this paper we use molecular biology techniques which permit a rapid screening and typing of high risk HPVs in clinical specimens. The screening procedure is based on the very sensitive method of polymerase chain reaction. Using a set of general primers derived from the E1 open reading frame, which anneal to a large variety of human papilloma virus DNA, we can classify samples into positive or negative for the presence of HPV sequences in a single step. The typing of the high risk HPV types is achieved by restriction enzyme analysis using the endonuclease Alu I which cleaves each high risk HPV type at different sites, thus permitting the easy identification of each type after agarose gel electrophoresis.
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PMID:A rapid method for the screening and typing of high risk HPVs using molecular biology techniques. 857

A method for real-time fluorescent detection and quantification of nucleic acid amplification using a restriction endonuclease was developed. In this homogeneous system detection is mediated by a primer containing a reporter and quencher moiety at its 5' terminus separated by a short section of DNA encoding a restriction enzyme recognition sequence. In the single stranded form, the signal from the fluorescent reporter is quenched due to fluorescence resonance energy transfer. However, as the primer becomes incorporated into a double stranded amplicon, a restriction enzyme present in the reaction cleaves the DNA linking the reporter and quencher, allowing unrestricted fluorescence of the reporter. To test this system, a primer specific for the E6 gene of human papilloma virus (HPV) 16 was combined with the cleavable energy transfer label and used to amplify HPV16 positive DNA. In the presence of the thermally stable restriction enzyme BstNI, the reporter system was found to generate a fluorescent signal in proportion to the amount of template DNA. In addition to this direct format, the reporter primer was also used to monitor and quantify the amplification of other sequences. This was accomplished by using primers that contain a tag sequence complementary to the reporter oligonucleotide.
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PMID:Homogeneous real-time detection and quantification of nucleic acid amplification using restriction enzyme digestion. 1514 92

Telomerase activity and human telomerase reverse transcriptase (hTERT) mRNA expression were investigated in cervical specimens and were correlated with cytologic findings and the presence of human papilloma virus (HPV) infection. Telomerase activity was evaluated by the telomeric repeat protocol assay and hTERT mRNA expression was evaluated by reverse transcriptase polymerase chain reaction (PCR). HPV DNA was detected by PCR, as well as restriction endonuclease digestion. HPV DNA was detected in all 82 specimens with abnormal cytologic findings and in 4 of 34 normal samples. Low-grade squamous intraepithelial lesions (LGSILs) were present in 74 of 82 specimens (90.2%) and high-grade squamous intraepithelial lesions (HGSILs) were present in 8 of 82 (9.75%) specimens. Seven of the eight HGSIL (87.5%) and 26 of 74 LGSIL (35.1%) specimens were hTERT positive, whereas all normal specimens were hTERT mRNA negative. Telomerase activity was detected in 21 of 74 (28.4%) LGSIL/atypical squamous epithelial cells of undetermined significance (ASCUS) and in five of eight (62.5%) HGSIL samples. A correlation was observed among telomerase activity, hTERT mRNA expression, and high-risk HPV infection in HGSIL samples (P < 0.001). High-risk HPV infection assessment showed 75% sensitivity and 72.2% specificity for HGSILs. Telomerase activity assessment in cervical smears showed sensitivity and negative predictive value (NPV) for HGSILs 62.5% and 96.7%, whereas specificity and positive predictive value (PPV) were 80.5% and 19.2%, respectively. hTERT mRNA expression assessment showed 87.5% sensitivity and 98.7% NPV for HGSILs, whereas specificity and PPV were 76% and 21.2%, respectively. Based on the above-described telomerase assessment values, it is suggested that the telomerase system might not be an appropriate diagnostic marker for cytology, given that the final evaluation must rely on a combination of all available test assessment data, clinical diagnosis, as well as the follow-up of all LGSIL samples that were positive for telomerase activation.
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PMID:The role of human telomerase catalytic subunit mRNA expression in cervical dysplasias. 1579 48

A tissue-specific promoter can control downstream gene expression in tissues or organs. The human involucrin (hINV) promoter (pINV) that contains 2474 bp of hINV upstream sequence is able to regulate tissue-specific gene expression. This tissue specificity may be important for the prevention and treatment of human papilloma virus infections. pINV was cloned by polymerase chain reaction and the human papillomavirus (HPV)16 E6/7 gene was obtained from the cancer tissue samples of patients with cervical carcinoma at the Yangzhou Maternal and China Health-Care Center of Jinagsu Province (Yangzhou, China). First, specific primers were designed according to the genomic DNA sequence of the HPV16-type standard strain that has been reported and the E6/7 gene was acquired by PCR. The carcinogenic fraction of the E6/7 gene was removed and the remaining section was cloned into T vectors, sequenced correctly and then cloned into the eukaryotic expression vector pCEP4, which was lacking the CMV promoter. The positive recombinants were identified using blue-white screening and endonuclease digestion, subsequent to sequencing and analysis, and the tissue-specific recombinant pINV-HPV16E6/7 plasmids was detected.
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PMID:Construction and detection of the tissue-specific pINV-HPV16 E6/7 vector. 2562 Oct 60