Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0038362 (stomatitis)
 8,852 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Previous work has shown that the mRNA encoding the vesicular stomatitis virus (VSV) glycoprotein (G) is bound to the rough endoplasmic reticulum (RER) and that newly made G protein is localized to the RER. In this paper, we have investigated the topology and processing of the newly synthesized G protein in microsomal vesicles. G was labeled with [35S]methionine ([35S]met), either by pulse-labeling infected cells or by allowing membrane-bound polysomes containing nascent G polipeptides to complete G synthesis in vitro. In either case, digestion of microsomal vesicles with any of several proteases removes approximately 5% (30 amino acids) from each G molecule. These proteases will digest the entire G protein if detergents are present during digestion. Using the method of Dintzis (1961, Proc. Natl. Acad. Sci. U. S. A. 47:247--261) to order tryptic peptides (8), we show that peptides lost from G protein by protease treatment of closed vesicles are derived from the carboxyterminus of the molecule. The newly made VSV G in microsomal membranes is glycosylated. If carbohydrate is removed by glycosidases, the resultant peptide migrates more rapidly on polyacrylamide gels than the unglycosylated, G0, form synthesized in cell-free systems in the absence of membranes. We infer that some proteolytic cleavage of the polypeptide backbone is associated with membrane insertion of G. Further, our findings demonstrate that, soon after synthesis, G is found in a transmembrane, asymmetric orientation in microsomal membranes, with its carboxyterminus exposed to the extracisternal, or cytoplasmic, face of the vesicles, and with most or all of its amino-terminal peptides and its carbohydrate sequestered within the bilayer and lumen of the microsomes.
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PMID:Transmembrane biogenesis of the vesicular stomatitis virus glycoprotein. 22 71

Affinity chromatography on columns containing globin mRNA, R17 phage mRNA, or double-stranded RNA linked to cellose is used to demonstrate unequivocally that the eukaryotic initiation factor (eIF-2) that forms a ternary complex with Met-tRNAf and GTP also binds tightly to these RNA species. Affinity chromatography of reticulocyte ribosomal wash yields over 100-fold purification of Met-tRNAf-binding factor. This factor is eluted as one of the most tightly bound proteins, and is active in protein synthesis even after passage over a column of double-stranded RNA-cellulose. eIF-2 binds mRNA and double-stranded RNA in distinctly different modes, protecting essentially all sequences in double stranded RNA, but very few in mRNA, against digestion with ribonuclease. Apparently, eIF-2 recognized the A conformation of double-stranded RNA, but not its sequence. By contrast, globin, Mengo virus, R17 and vesicular stomatitis virus mRNA are shown to possess a high-affinity binding site for eIF-2 that is absent in negative-strand RNA of vesicular stomatitis virus, an RNA that cannot serve as messenger. The results support the concept that eIF-2, the initiation factor that binds Met-tRNAf, recognizes an internal sequence in mRNA essential for protein synthesis.
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PMID:Specific binding of messenger RNA and methionyl-tRNAfMet by the same initiation factor for eukaryotic protein synthesis. 27 36

An RNA-dependent RNA polymerase activity has been demonstrated for spring viremia of carp virus (SVCV). The optimal temperature for in vitro synthesis of RNA was 20 to 25 degrees C. The SVCV enzyme activity was stimulated when the methyl donor S-adenosyl-L-methionine was included in the reaction mixture. S-adenosyl-L-methionine was not particularly effective in stimulating the virion RNA polymerase activity of vesicular stomatitis virus or pike fry rhabdovirus. The 5' nucleotide of the SVCV viral RNA is pppAp.
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PMID:Spring viremia of carp virus RNA and virion-associated transcriptase activity. 56 17

TsO82, a spontaneous temperature-sensitive (ts) mutant of vesicular stomatitis virus (VSV) isolated in chick embryo fibroblasts (CEFs), complements the five prototype ts mutants of the virus. The data presented here indicate that the defect in tsO82 is localized in the M gene. The mutation changed a methionine to an arginine at position 51 of the M protein. Only true revertants could be isolated, and their frequency was low, perhaps due to the type of substitution required to return to the wild-type phenotype. TsO82 does not exhibit hypertranscription, in contrast to the data reported for all of the other ts mutants affected in the M protein. Moreover, tsO82 is conditionally ts, since it grows normally in BHK-21 cells at all temperatures. It exhibits no c.p.e. at the non-permissive temperature in CEFs. Our data argue for multiple functions of the M protein of VSV, the domain affected by the tsO82 mutation possibly being implicated both in the shut-off of cellular RNA synthesis, and for the recognition of a cellular factor required for efficient viral RNA synthesis.
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PMID:Genetic evidence for multiple functions of the matrix protein of vesicular stomatitis virus. 215 8

Equine interferon-beta 1 (EqIFN-beta 1) was purified from extracts of recombinant Escherichia coli by sequential chromatography on hydroxylapatite, anion-, and cation-exchangers. The resulting protein was greater than 98% pure as determined by sodium dodecylsulfate gel electrophoresis, gel permeation HPLC, and reverse-phase HPLC. Amino-terminal amino acid sequencing revealed that essentially all molecules contained an additional amino-terminal methionine. The specific antiviral activity of EqIFN-beta 1 determined on equine dermal fibroblasts challenged with vesicular stomatitis virus (VSV) was approximately 5 X 10(8) U/mg. Less than 0.001% of this activity was observed in antiviral assays using human (A549), murine (L-M), ovine (SCP), or bovine (MDBK and BT) cells challenged with VSV or encephalomyocarditis virus. A series of monoclonal murine IgG antibodies were developed which neutralize the antiviral activity of EqIFN-beta 1. None of these antibodies nor rabbit antiserum to EqIFN-beta 1 were able to neutralize human IFN-beta; antiserum to human IFN-beta did not neutralize EqIFN-beta 1. Two of the monoclonal antibodies were used to establish a rapid one-step solid-phase enzyme immunoassay for EqIFN-beta 1.
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PMID:Recombinant equine interferon-beta 1: purification and preliminary characterization. 220 Aug 32

Antiviral activity has been found in conceptus and placental tissues in numerous species, including mice, pigs, sheep, cattle and humans. In sheep and cattle, the antiviral activity is due to an interferon alpha (IFN-alpha), but in other species the nature of the protein(s) responsible for placental activity is unknown. The objectives of this study were to determine if the constitutive antiviral activity associated with the mouse conceptus is produced as early as the peri-implantation period, and to determine if the activity is due to an IFN-alpha or -beta. Conceptus and placental tissue explants released antiviral activity from Day 4 through at least Day 16 of gestation as measured in an agar overlay bioassay employing CHO cells challenged with vesicular stomatitis virus. This activity was neutralized by antiserum against MuIFN-alpha/beta. The same antiserum failed, however, to immunoprecipitate radiolabeled proteins from medium collected from Day 4 blastocysts cultured in the presence of L-[35S]-methionine. S1 nuclease analysis of placental RNA and screening of ectoplacental cone and extraembryonic ectoderm cDNA libraries with MuIFN-alpha and -beta probes failed to detect IFN related mRNAs, even under relatively non-stringent conditions of hybridization. Thus, while antiviral activity is produced by peri-implantation conceptuses in several diverse mammalian species, it does not appear to be due to a conserved type of IFN in all these species.
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PMID:Characterization of the antiviral activity constitutively produced by murine conceptuses: absence of placental mRNAs for interferon alpha and beta. 237 95

Papaverine, an inhibitor of cAMP phosphodiesterase, reduced yields of infectious vesicular stomatitis virus in HEp-2 cells approximately 100-fold if added to cultures at a concentration of 30 microM before and after virus infection. The extent of papaverine-induced suppression of viral growth was dependent on drug dose and treatment regimen. Cells progressively recovered their viral permissive state after removal of drug. The cyclic nucleotide, cGMP, nullified the inhibitory effect of papaverine if added to cells during drug treatment. Pulse labeling experiments with [35S]methionine showed that papaverine compromises production of all virus-specific proteins in infected cells without adversely affecting host cell protein synthesis. Treatment of cells with papaverine strongly inhibited the production of viral RNA and both cellular RNA and DNA. It was found that VSV causes an immediate but transient stimulation of DNA synthesis in HEp-2 cells which is prevented by papaverine treatment. This drug also selectively blocked primary transcription of VSV in vivo and to a lesser extent in vitro RNA polymerase activity of the virion-bound transcriptase. The finding that papaverine has a strong inhibitory effect on viral biosynthesis including early transcription suggests that VSV replication may depend on host factors that regulate intracellular levels of cyclic nucleotides such as cAMP.
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PMID:Inhibitory effect of papaverine on RNA and protein synthesis of vesicular stomatitis virus. 241 Oct 62

Recombinant DNA techniques were used to delete regions of a cDNA clone of the phosphoprotein NS gene of vesicular stomatitis virus. The complete NS gene and four mutant genes containing internal or terminal deletions were inserted into a modified pGem4 vector under the transcriptional control of the phage T7 promoter. Run-off transcripts were synthesized and translated in vitro to provide [35S]methionine-labeled complete NS or deletion mutant NS proteins. Immune coprecipitation assays involving these proteins were developed to map the regions of the NS protein responsible for binding to the structural viral nucleocapsid protein N and the catalytic RNA polymerase protein L. The data indicate the NS protein is a bivalent protein consisting of two discrete functional domains. Contrary to previous suggestions, the negatively charged amino-terminal half of NS protein binds to L protein, while the carboxyl-terminal half of NS protein binds to both soluble recombinant nucleocapsid protein N and viral ribonucleocapsid template.
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PMID:Location of the binding domains for the RNA polymerase L and the ribonucleocapsid template within different halves of the NS phosphoprotein of vesicular stomatitis virus. 244 89

The growth of vesicular stomatitis virus (VSV) can be inhibited by the antiviral compound tricyclo-decane-9-yl-xanthogenate (D609). On analysing the antiviral mechanism we found no effect on the primary transcription of infecting VSV genomes. In contrast, the processes of replication and transcription during late stages of infection were inhibited. Despite the synthesis of all five virus-coded proteins (41% to 56% of the uninhibited control), as shown by labelling with [35S]methionine, the phosphorylation of the non-structural (NS) protein was reduced in the presence of the xanthate by a factor of at least 17. The pattern of phosphorylation of the bulk of cellular proteins remained unaltered under the same conditions. A relation between a possible loss of biological activity of the NS protein owing to the lack of phosphorylation and the decreased VSV RNA synthesis is suggested.
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PMID:Inhibition of the phosphorylation of the regulatory non-structural protein of vesicular stomatitis virus by an antiviral xanthate compound. 244 22

Caco-2 cells, derived from human colon, have the morphological, functional, and biochemical properties of small intestinal epithelial cells. After infection with enveloped viruses, influenza virions assembled at the apical plasma membrane while vesicular stomatitis virus (VSV) particles appeared exclusively at the basolateral membrane, similar to the pattern observed in virus-infected Madin-Darby canine kidney (MDCK). When grown in Millicell filter chamber devices and labeled with [35S]methionine, Caco-2 monolayers released all of their radiolabeled secretory products preferentially into the basal chamber. Among the proteins identified were apolipoproteins AI and E, transferrin, and alpha-fetoprotein. No proteins were observed to be secreted preferentially from the apical cell surface. The lysosomal enzyme beta-hexosaminidase was also secreted primarily from the basolateral surface of the cells in the presence or absence of lysosomotropic drugs or tunicamycin, which inhibit the targetting of lysosomal enzymes to lysosomes. Neither of these drug treatments significantly affected the polarized secretion of other nonlysosomal proteins. In addition, growth hormone (GH), which is released in a nonpolar fashion from MDCK cells, was secreted exclusively from the basolateral membrane after transfection of Caco-2 cells with GH cDNA in a pSV2-based expression vector. Similar results were obtained in transient expression experiments and after selection of permanently transformed Caco-2 cells expressing GH. Since both beta-hexosaminidase and GH would be expected to lack sorting signals for polarized exocytosis in epithelial cells, these results indicate that in intestinal cells, proteins transported via the basolateral secretory pathway need not have specific sorting signals.
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PMID:A specific sorting signal is not required for the polarized secretion of newly synthesized proteins from cultured intestinal epithelial cells. 245 57


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