Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0017160 (gastroenteritis)
 11,398 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The Spike (S) protein from a virulent British field isolate of porcine transmissible gastroenteritis virus (TGEV) FS772/70 was constructed from cDNA and inserted into the vaccinia virus (VV) thymidine kinase gene locus under the control of the VV early/late gene P7.5k promoter. Recombinant S protein was synthesized as an endo-beta-N-acetylglucosaminidase H (Endo H)-sensitive glycoprotein with high mannose simple oligosaccharides (gp 190) that underwent post-translational modification to an Endo H-resistant glycoprotein with complex oligosaccharides (gp210). Immunofluorescence analysis demonstrated that the majority of recombinant S protein was retained at the Golgi but some S protein was expressed on the plasma membrane. Monoclonal antibodies (mAbs) raised against native S protein reacted with this recombinant S protein; also, mice infected with the recombinant vaccinia virus (rVV) expressing the S protein induced TGEV neutralizing antibodies. A truncated S protein (S delta) was also expressed in rVV-infected cells by introducing a deletion into the S protein cDNA that removed 292 amino acids from the C-terminus. The S delta protein (gp 170) was shown to be antigenically similar to TGEV S protein by immunofluorescence and immunoprecipitation tests but was retained in the endoplasmic reticulum and not expressed on the cell surface.
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PMID:Intracellular processing of the porcine coronavirus transmissible gastroenteritis virus spike protein expressed by recombinant vaccinia virus. 185 Sep 27

In 1984 neutralizing antibodies against transmissible gastroenteritis virus (TGEV) were detected in pig herds in a small geographical area in the southern part of Denmark. No clinical symptoms were observed and accumulating epidemiological evidence gradually pointed towards a respiratory infection. In 1986 a TGE-like virus, tentatively named porcine respiratory coronavirus (PRCV), was isolated from the lungs of swine. The virus was partially characterized using monoclonal antibodies against TGEV and this showed that some (mainly nonneutralizing) epitopes of the peplomer glycoprotein E2 were absent in PRCV, whereas the major neutralizing domains were conserved. These findings allowed the design of competitive antibody immunoassays either discriminating or not discriminating the immune responses against the two viruses. However, the discriminating epitopes studied so far have shown minor immunodominance and some steric interference from nondiscriminating epitopes.
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PMID:Infection with a new porcine respiratory coronavirus in Denmark: serologic differentiation from transmissible gastroenteritis virus using monoclonal antibodies. 196 35

Four antigenic sites of the E2 glycoprotein of transmissible gastroenteritis virus were defined by competitive radioimmunoassays of monoclonal antibodies (MAbs). Here, we describe the localization of these sites by testing the antigenicity of protein fragments and prokaryotic expression products of E2 gene fragments, and by sequencing of MAb-resistant (mar) mutants. Partial proteolysis of purified E2 protein allowed the isolation of a 28K fragment recognized by both site A- and site C-specific MAbs. An antiserum against this fragment bound to a synthetic peptide containing residues 1 to 18 and to an expression product containing residues 1 to 325. The same expression product was recognized by site C-specific MAbs. These data indicate that residues within the sequence 1 to 325 contribute to site C and possibly also to site A. Sequencing of mar mutants that escaped neutralization by site A-specific MAbs indicated that residues 538 and 543 also belong to site A. The binding of site-specific MAbs to expression products led directly to the localization of sites B and D, between residues 1 to 325 and 379 to 529, respectively. The first 37% of the polypeptide chain of E2 appears to be more immunogenic than the rest of the sequence.
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PMID:Localization of antigenic sites of the E2 glycoprotein of transmissible gastroenteritis coronavirus. 215 84

The causative agent (TGEV) of porcine transmissible gastroenteritis belongs to the Coronaviridae, a family of enveloped viruses with a positive, single-stranded RNA genome. Important progress has recently been made concerning the molecular biology of TGEV. The research work of our group has been focused on two main aspects: genome structure and functional domains of the envelope proteins. TGEV genomic RNA is organised into seven regions. The sequence of six of them, i.e. the 3' most 8300 nucleotides, has been established from cDNA clones. Three genes encoding the structural proteins, the peplomer protein E2, the transmembrane protein E1 and the nucleoprotein, have been identified. Additional open reading frames allowed for the prediction of four non-structural polypeptides, the role of which remains to be discovered. The remaining part of the genome (estimated length 20 kb) is thought to encode the polymerase. Expression of TGEV genes involves the production of six subgenomic mRNAs, which together with the virion RNA, form a 3' terminal nested set. The peplomer glycoprotein E2 (220 kDa) is 1431 residues long and highly glycosylated. Several domains were identified, including a C-terminal anchoring region and at least four major antigenic sites, which cluster in the amino half part of the molecule. Two sites containing most of the critical neutralisation determinants are highly conserved among TGEV strains. The glycoprotein E1 (29kDa) is mostly embedded in the membrane and plays a crucial role in the virion architecture. However, a short N-terminal domain protruding out of the particle mediates complement-dependent neutralisation, and induces alpha interferon synthesis, likely through a direct interaction with the lymphocyte membrane.
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PMID:Molecular biology of transmissible gastroenteritis virus. 216 70

The folding and oligomerization of coronavirus spike protein were explored using a panel of monoclonal antibodies. Chemical cross-linking and sedimentation experiments showed that the spike of transmissible gastroenteritis virus is a homotrimer of the S membrane glycoprotein. The spike protein was synthesized as a 175,000-apparent-molecular-weight (175K) monomer subunit that is sensitive to endo-beta-N-acetylglucosaminidase H. Assembly of monomers into a trimeric structure was found to occur on a partially trimmed polypeptide and to be a rate-limiting step, since large amounts of monomers failed to trimerize 1 h after completion of synthesis. Terminal glycosylation of newly assembled trimers, resulting in the biosynthesis of three 220K oligomers, occurred with a half time of approximately 20 min. Monomeric (230K to 240K) processed forms were also observed in cells and in virions. The 175K monomeric form expressed four major antigenic sites previously localized within the amino-terminal half of the S polypeptide chain; however, two classes of trimer-restricted epitopes (borne by three 220K and/or three 175K oligomers) were identified. The S glycoprotein of coronavirus might be a valuable model system for discovering new aspects of the maturation of membrane glycoproteins.
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PMID:Assembly of coronavirus spike protein into trimers and its role in epitope expression. 217 Jun 76

The genome organization of porcine respiratory coronavirus (PRCV), a newly recognized agent which has a close antigenic relationship to the enteropathogenic transmissible gastroenteritis virus (TGEV), was studied. Genomic RNA from cell-cultured PRCV (French isolate RM4) was used to produce cDNA clones covering the genomic 3' end to the start of the spike (S) glycoprotein gene (7519 nucleotides). Six open reading frames (ORFs) were identified that allowed the translation of three coronavirus structural proteins and three putative non-structural (NS) polypeptides, homologous to TGEV ORFs designated NS3-1, NS4 and NS7. Pairwise alignment of PRCV nucleotide and amino acid sequences with sequence data available for three TGEV strains revealed a 96% overall homology. However, the genome of PRCV exhibited two important distinctive features. The first was that the S gene lacked 672 nucleotides in the 5' region and encoded a truncated form of the S polypeptide, and secondly, the first NS ORF downstream of the S gene was predicted to be non-functional as a consequence of a double deletion. The significance of genomic deletions with respect to tissue tropism and evolution of coronaviruses is discussed.
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PMID:Porcine respiratory coronavirus differs from transmissible gastroenteritis virus by a few genomic deletions. 217 56

The gene encoding the spike glycoprotein of the human coronavirus HCV 229E has been cloned and sequenced. This analysis predicts an S polypeptide of 1173 amino acids with an Mr of 128,600. The polypeptide has 30 potential N-glycosylation sites. A number of structural features typical of coronavirus S proteins can be recognized, including a signal sequence, a membrane anchor, heptad repeat structures and a carboxy-terminal cysteine cluster. A detailed, computer-aided comparison with the S proteins of infectious bronchitis virus, feline infectious peritonitis virus, transmissible gastroenteritis virus and murine hepatitis virus, strain JHM is presented. We have also done a Northern blot analysis of viral RNAs in HCV 229E-infected cells using synthetic oligonucleotides. On the basis of this analysis, and by analogy to the replication strategy of other coronaviruses, we are able to propose a model for the organization and expression of the HCV 229E genome.
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PMID:Nucleotide sequence of the gene encoding the spike glycoprotein of human coronavirus HCV 229E. 234 67

The antigenic structure of the peplomer glycoprotein E2 of the porcine transmissible gastroenteritis coronavirus (TGEV) was explored using a panel of 23 hybridoma antibodies (MAbs). The topography of the epitopes was established by means of a competition radioimmunoassay. Four main antigenic sites, termed A, B, C and D, were thus clearly delineated. Most of the neutralization-mediating determinants were found to cluster in the A-B area, which has been shown to be highly conserved among TGEV strains. Cooperative enhancement of binding to sites B and D was observed following attachment of MAbs relevant to site A. Additional epitopes were identified on E2 by MAbs that selectively recognized its intracellular precursor. Functional mapping was also performed using neutralization-resistant variants. Analysis of their reactivity confirmed part of the epitope linkages defined by the first approach. The overall lower frequency of such variants altered at site A suggested that some of the epitopes may play an essential function.
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PMID:Antigenic structure of transmissible gastroenteritis virus. II. Domains in the peplomer glycoprotein. 242 49

Purified transmissible gastroenteritis (TGE) virus was found to be composed of three major structural proteins having relative molecular weights of 200,000, 48,000, and 28,000. The peplomer glycoprotein was purified by affinity chromatography with the monoclonal antibody (MAb) 1D.G3. A collection of 48 MAbs against TGE virus was developed from which 26, 10, and 3 were specific for proteins E2, N, and E1, respectively. A total of 14 neutralizing MAbs of known reactivity were E2 protein specific. In addition, MAb 1B.C11, of unknown specificity, was also neutralizing. These MAbs reduced the virus titer 10(2)- to 10(9)-fold. Six different epitopes critical in TGE virus neutralization were found, all of which were conformational based on their immunogenicity and antigenicity. Only the epitope defined by MAb 1G.A7 was resistant to sodium dodecyl sulfate treatment, although it was destroyed by incubation in the presence of both the detergent and beta-mercaptoethanol. The frequency of MAb-resistant (mar) mutants selected with four MAbs (1G.A7, 1B.C11, 1G.A6, and 1E.F9) ranged from 10(-6) to 10(-7), whereas the frequency of the putative mar mutant defined by MAb 1B.B11 was lower than 10(-9). Furthermore, the epitopes defined by these MAbs and by MAbs 1H.C2 and 1A.F10, were present in 11 viral isolated with different geographical locations, years of isolation, and passage numbers (with the exception of two epitopes absent or modified in the TOY 56 viral isolate), suggesting that the critical epitopes in TGE virus neutralization were highly conserved.
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PMID:Critical epitopes in transmissible gastroenteritis virus neutralization. 242 44

Fecal rotaviruses collected from October 1983 to September 1984 from outpatients and inpatients attending the Royal Children's Hospital, Melbourne, Australia, with acute gastroenteritis were serotyped by enzyme immunoassay using rotavirus-neutralizing mouse monoclonal antibodies specific for serotypes 1 to 4. Application of three different serotype 1-neutralizing antibodies indicated variations in neutralization epitopes between serotype 1 rotaviruses on the major outer capsid glycoprotein, including a site shared with serotype 3 rotaviruses. The three different binding patterns observed were termed "monotypes." Comparison of monotype and serotype with genomic RNA profiles generated by gel electrophoresis of ds viral RNA indicated that each RNA electropherotype corresponded to only one monotype (1a, 1b, 1c) or serotype (3, 4). However, serotypes 1 (a and c) and 4 contained multiple electropherotypes. Greater numbers of RNA segment variations, including alteration in mobility of gene segments 7, 8, and 9, were evident between rotaviruses of different serotype or monotype than within those groups. Within limits of time and location, rotavirus neutralization epitope variations appear to correlate with RNA polymorphism. Where rotavirus epidemiology has been analyzed by year using RNA electropherotypes, only limited numbers of each RNA pattern need to be serotyped to ascertain the major serotypes in circulation.
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PMID:Variation in neutralization epitopes of human rotaviruses in relation to genomic RNA polymorphism. 244 19


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