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)

The variability of herpes simplex viruses has been measured using the RNAse A mismatch cleavage method in two genes: thymidine kinase and glycoprotein B of both HSV-1 and HSV-2. This technique permitted us to study the variability of the virus with a greater level of resolution than restriction endonuclease analysis. The phylogenetic trees obtained for the different genes allowed us to identify consistent clusters of viruses circulating in the same geographical area. Our results showed that thymidine kinase is more heterogeneous than glycoprotein B for both subtypes of HSV, and confirmed that HSV-1 is more heterogeneous than HSV-2 for both genes. This is the first time that this kind of analysis has been applied to DNA viruses.
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PMID:Comparative study of the genetic variability in thymidine kinase and glycoprotein B genes of herpes simplex viruses by the RNase A mismatch cleavage method. 776 93

The development of PCR assays for detection of BHV-1, BRSV, BVDV and another pestiviruses is summarized. A polymerase chain reaction assay based on primers selected from the viral gI glycoprotein gene detected 3 fg pure BHV-1 DNA, 0.1-1.0 TCID50 or a single infected cell. No amplification was observed with DNA from BHV-2, BHV-3, BHV-4, OHV-1 or OHV-2. However, a fragment of the correct size (468 bp) was amplified using DNA from herpesviruses isolated from reindeer, red deer and goat. The PCR assay was able to detect virus in nasal swabs 1-14 days after experimental infection of cattle and there was a good correlation when PCR was compared to virus isolation for the detection of BHV-1 in clinical field samples. Detection of BHV-1 in fetal bovine serum and semen samples was also successful. PCR detecting a broad range of BVDV, BDV and HCV was developed. Of six sets of primers selected from different parts of the pestivirus genome the best results were provided by a pair 324/326 from the highly conserved 5'-non-coding region which gave an amplification with all 129 isolates tested. This panel consisted of 79 isolates from cattle, 33 from pigs and 17 from sheep. Differentiation between viruses was achieved by cleavage of the PCR-amplified products (288 bp) with the restriction endonucleases AvaI and BglI. The BVDV products were cleaved by AvaI, HCV by BglI and AvaI. Both enzymes, AvaI and BglI, did not cut the BDV products. A nested polymerase chain reaction assay was developed for the detection of bovine respiratory syncytial virus (BRSV). Primers were selected from the gene encoding the F fusion protein. The sensitivity of PCR assay was 0.1 TCID50. No cross reaction was observed with nine heterologous respiratory viruses. PCR products of bovine and human RSV strains were discriminated using endonuclease ScaI, which specifically cleaved products of BRSV. PCR assay detected BRSV in nasal swabs collected from cattle in the acute stage of respiratory disease. In vitro amplification detected 31 positive samples of 35 while immunofluorescence only 23 samples.
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PMID:[Development of PCR tests for the detection of bovine herpesvirus-1, bovine respiratory syncytial viruses and pestiviruses]. 781 1

Rabies persists in Ontario wildlife in two predominant species: the red fox (Vulpes vulpes) and the striped skunk (Mephitis mephitis). A protocol applying reverse transcription/polymerase chain reaction (RT/PCR) and restriction endonuclease analysis (REA) to the rabies virus nucleoprotein gene was previously reported by Nadin-Davis et al. (Journal of General Virology 74, 829-837, 1993) to be useful for discrimination of rabies virus variants in Ontario. Four main types, which showed no host species specificity but which did exhibit different geographical distributions, were identified. Between 1989 and 1992 an area north and west of the city of North Bay experienced unusual and substantial rabies activity. In this report we describe the use of these molecular techniques to investigate the epidemiology of this recent rabies outbreak in central Ontario. It is shown that two of the four previously identified variants had invaded this region from the south and east, but in addition viruses very closely related to arctic isolates of rabies virus were found. The nucleoprotein and glycoprotein genes of this arctic type were sequenced and compared to those of its more southerly neighbours.
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PMID:A molecular epidemiological study of rabies virus in central Ontario and western Quebec. 793 Nov 45

The varicella-zoster virus (VZV) glycoprotein B (gB) is a major viral antigen which elicits immunity and neutralizing antibodies. In this study, the genomic map position and DNA sequence of a simian varicella virus (SVV) homologue of the VZV gB gene was identified and the transcript analysed. A 32P-labelled VZV gB DNA probe hybridized to a subclone of the SVV BamHI B restriction endonuclease fragment indicating the fine map position of SVV DNA sequences homologous to the VZV gB gene. The SVV gB DNA sequence was determined and analysis revealed a 2751 base pair open reading frame (ORF) with 71.1% identity to the VZV gB gene and 53.8% identity to the herpes simplex type 1 gB gene. The SVV gB ORF encodes a 916 amino acid polypeptide with a predicted molecular mass of 104K. The deduced SVV and VZV gB polypeptides share 78.9% amino acid identity and predicted N-linked glycosylation sites, cleavage sites and transmembrane regions. 32P-labelled SVV gB DNA and RNA probes hybridized to a 3.5 kilobase SVV polyadenylated transcript. Primer extension experiments identified transcript start sites for the SVV and VZV gB genes and permitted a comparison of the sequences upstream of the SVV and VZV gB ORFs. The SVV and VZV gB promoter elements are similar in content and align closely. The VZV gB transcript start site suggests a gB polypeptide initiation site which is inconsistent with the previously reported ATG start codon.
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PMID:DNA sequence and transcriptional analysis of the simian varicella virus glycoprotein B gene. 796 32

The susceptibility of three avian cell lines (IQ1A, LMH, and QT-35) to infection by three strains of infectious laryngotracheitis virus (ILTV) was assessed both visually and by hybridization using an ILTV glycoprotein B gene probe. In the chicken liver tumor cell line (LMH), cytopathogenicity was observed at the second passage, and plaque formation was observed at the third passage. The identity of the infectious agent was verified to be ILTV by restriction endonuclease analysis of the virus genome and subsequent Southern hybridization. In contrast to LMH cells, which were a suitable host for ILTV, the quail cell line (IQ1A) was refractory to infection by this virus. Moreover, although LMH cell-adapted ILTV could initially replicate to a limited extent in the other quail cell line (QT-35), this ability was not sustained upon continual passaging.
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PMID:Propagation of infectious laryngotracheitis virus in an avian liver cell line. 798 Feb 66

Sets of primers were designed which enabled specific amplification of homologous regions of the glycoprotein C and gene 76 genetic loci of equine herpesviruses 1 and 4 (EHV-1 and EHV-4). The resultant virus-specific polymerase chain reaction (PCR) products arising from each loci could be discriminated easily on the basis of size on an agarose gel, allowing rapid differentiation of the two equine herpesviruses. Specificity of the amplifications were confirmed by Southern hybridization and restriction endonuclease digestion. The PCR test was applied to nasal swab samples from weanling foals and to archival aborted fetal tissue samples and the results compared to those obtained by virus isolation. A strong correlation was found between this PCR assay and virus isolation methods of EHV-1 and EHV-4 detection and discrimination.
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PMID:Rapid, single-step differentiation of equid herpesviruses 1 and 4 from clinical material using the polymerase chain reaction and virus-specific primers. 805 Dec 34

Apolipoprotein E (apo E) is a polymorphic glycoprotein that plays an essential part in the binding to receptors for the uptake of chylomicrons and VLDL remnants and of LDL. The three major isoforms are E3 (Cys112/Arg158), E4 (Arg112/Arg158) and E2 (Cys112/Cys158). The apo E genetic variation has a great impact. In most of type III familial hyperlipoproteinemias (HLP), E2 is implicated at the homozygote status. In other cases, rare alleles are directly responsible for dominant type III HLP. Apo E polymorphism is an essential determinant in the interindividual variations of lipids in healthy subjects in various populations. Its influence can be significant on the efficacy of nutritional or therapeutic interventions. The allele epsilon 4 appears to be associated with an increased risk of premature atherosclerosis. Recently, epsilon 4 was demonstrated to be associated with an early Alzheimer's disease onset. Apo E polymorphism contributes to the lipid disorders in diabetes and obesity. The analysis of apo E polymorphism can be carried out with two conceptually different approaches. The first one is based on the separation of plasma isoforms of the protein by isoelectric focusing or bidimensional electrophoresis. The other one consists in the application of molecular biology techniques (PCR and endonuclease restriction profiles) for a detection of the common alleles and of several rare alleles, avoiding the possible errors of the phenotyping technique of the apo E protein. The application of genetic engineering allows a better understanding of the role played by apo E towards its receptors and in other molecular interactions which are not well known up to now.
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PMID:[Pathology of the human apolipoprotein E gene]. 807 81

Bovine herpesviruses (BHV) are associated with a variety of clinical syndromes. Bovine herpesvirus 1 isolates were placed into three genome subtypes based on restriction endonuclease analyses, which were loosely associated by clinical manifestation as BHV1.1 (respiratory), BHV1.2 (genital), and BHV1.3 (encephalitic). More recently the encephalitic isolate has been classified BHV5. A comparison of the cytopathic effect (CPE) in fetal bovine lung cell cultures in the presence of cycloheximide showed that BHV1.1 and 1.2 isolates produced elongated, spindle-shaped CPE, whereas BHV5 produced more syncytial-like CPE. Each BHV-1 subtype synthesized four immediate-early transcripts. The sizes in kb were: 1.6, 3.4, 5.8, 7.5 (BHV1.1); 1.8, 3.6, 5.8, 7.5 (BHV1.2); and 1.8, 3.6, 5.8, 8.6 (BHV5). These transcripts were mapped to the inverted repeat region of each isolate by Southern blot hybridization using cDNA prepared from cycloheximide-treated BHV1-infected cellular polyA RNA. A possible unique immediate-early RNA may be produced by the BHV5 encephalitic isolate from an area of the internal repeat region unique to this isolate. Hybridization analysis using BHV1.1 cloned probes of the immediate-early protein gene, thymidine kinase gene, DNA binding/DNA polymerase gene, and glycoprotein III gene provided information for mapping of these genes to the BHV5 encephalitic isolate.
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PMID:Immediate-early gene expression and gene mapping comparisons among isolates of bovine herpesvirus 1 and 5. 816 Mar 51

We previously reported on a variant of the herpes simplex type 1 (HSV-1) strain 17 syn+, named 17 hep syn, capable of forming giant polykaryocytes (syncytia) in tissue culture and which induced a striking alteration in the pathogenesis of infection in vivo. Following footpad inoculation of mice, 17 hep syn infection resulted in a marked clinicopathologic acute inflammatory response of the inoculated limb and mice died without antecedant limb paralysis typical of the wild-type 17 syn+ infection. The syncytial and pathogenic phenotypes were mapped to a cloned 670-base pair Kpnl-Pstl (0.345-0.351 map units) DNA fragment encoding the carboxy terminal portion of the glycoprotein B (gB). In this report, we focus on the genetics of the region of the 17 hep syn gB gene that conferred both the syncytial and pathogenic phenotypes to 17 syn+. Five 17 syn+ x 17 hep syn syncytial recombinant viruses, R1-R5, generated in marker transfer experiments with cloned 17 hep syn fragments containing gB sequences, produced 17 hep syn-like disease in mice. Sequence analysis of the Kpnl-Pstl fragment of 17 hep syn revealed a single base pair change when compared to the 17 syn+ sequence, predicting an alanine (GCC codon) to valine (GTC codon) amino acid substitution at residue 825 of the mature gB protein, plus loss of an Ncol restriction endonuclease site. Southern blot analysis of Ncol digests of viral DNAs showed that all of the recombinants except R4 contained the same mutation as 17 hep syn. The syncytial phenotype of R4 was, however, mapped to the same region as 17 hep syn and the other recombinants, and the DNA sequence of the 670-base pair Kpnl-Pstl clone of R4 revealed another single base pair change predicting a leucine (CTC codon) to histadine (CAC codon) amino acid substitution at residue 787 of gB. The mutant gBs did not effect viral growth as all of the recombinant viruses had similar in vitro replication kinetics to wild-type HSV-1. These data provide direct evidence that at least two mutations can exist in the carboxy terminus of gB of HSV-1 that promote syncytial formation in vitro and effect pathogenesis in vivo.
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PMID:Two novel single amino acid syncytial mutations in the carboxy terminus of glycoprotein B of herpes simplex virus type 1 confer a unique pathogenic phenotype. 839 Jul 47

A sensitive assay based on the polymerase chain reaction for the detection of Ockelbo virus RNA was developed. Two primer pairs from the gene coding for the E2 glycoprotein were chosen. By use of a nested strategy for the primers, as few as 1 to 10 PFU could be detected. The amplified products were visualized as bands of appropriate size on ethidium bromide-stained agarose gels. The primer pairs allowed amplification of several Ockelbo and Sindbis virus isolates but discriminated between these and other alphaviruses. Ockelbo virus RNA was detected in 4 of 10 skin biopsy specimens collected during the acute stage of the disease. The identities of the amplified products were confirmed by restriction endonuclease cleavage. Acute- and convalescent-phase sera as well as lymphocytes collected during the convalescent phase were negative by the polymerase chain reaction. No infectious virus could be recovered from any of the specimens.
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PMID:Detection of Ockelbo virus RNA in skin biopsies by polymerase chain reaction. 839 82


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