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)

Porcine transmissible gastroenteritis virus (TGEV) nucleoprotein and integral membrane protein genes were cloned into the vaccinia virus insertion vector, pGS20, in the correct orientation for expression under the control of the vaccinia P7.5K promoter. Recombinant vaccinia viruses were generated by in vivo homologous recombination of the insertion vector with the WR strain of vaccinia virus. Nucleoprotein (N) expressed by both recombinant vaccinia virus and TGEV had a relative molecular mass (Mr) of 47,000 and was susceptible to degradation at the C-terminus yielding discrete breakdown products. The integral membrane protein (M) expressed by a recombinant vaccinia virus and TGEV was sensitive to endoglycosidase H reducing the mature polypeptide of Mr 29,000 to a species of Mr 27,000. Expression of M by recombinant vaccinia virus was inhibited during early infection due to a cryptic vaccinia virus transcriptional termination signal within the TGEV coding sequence. Indirect immunofluorescence showed that both N and M were only localised in the cell cytoplasm of either TGEV or recombinant vaccinia virus immunoprecipitated specific TGEV antigens from lysates of TGEV infected cells but had little significant TGEV neutralising activity in vitro.
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PMID:Expression and cellular localisation of porcine transmissible gastroenteritis virus N and M proteins by recombinant vaccinia viruses. 164 5

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

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

Coronaviruses (CoV) mature by a budding process at intracellular membranes. Here we showed that the major surface protein S of a porcine CoV (transmissible gastroenteritis virus) is not transported to the cell surface but is retained intracellularly. Site-directed mutagenesis indicated that a tyrosine-dependent signal (YXXI) in the cytoplasmic tail is essential for intracellular localization of the S protein. Surface expression of mutant proteins was evident by immunofluorescence analysis and surface biotinylation. Intracellularly retained S proteins only contained endoglycosidase H-sensitive N-glycans, whereas mutant proteins that migrated to the plasma membrane acquired N-linked oligosaccharides of the complex type. Corresponding tyrosine residues are present in the cytoplasmic tails of the S proteins of other animal CoV but not in the tail portion of the S protein of severe acute respiratory syndrome (SARS)-CoV. Changing the SEPV tetrapeptide in the cytoplasmic tail to YEPI resulted in intracellular retention of the S protein of SARS-CoV. As the S proteins of CoV have receptor binding and fusion activities and are the main target of neutralizing antibodies, the differences in the transport behavior of the S proteins suggest different strategies in the virus host interactions between SARS-CoV and other coronaviruses.
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PMID:A novel sorting signal for intracellular localization is present in the S protein of a porcine coronavirus but absent from severe acute respiratory syndrome-associated coronavirus. 1530 15