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)

The cytoplasm of vesicular stomatitis virus (VSV)-infected BHK cells has been separated into a fraction containing the membrane-bound polysomes and the remaining supernatant fraction. Total poly(A)-containing RNA was isolated from each fraction and purified. A 17S class of VSV mRNA was found associated almost exclusively with the membrane-bound polysomes, whereas 14,5S and 12S RNAs were found mostly in the postmembrane cytoplasmic supernatant. Poly(A)-containing VSV RNA synthesized in vitro by purified virus was resolved into the same size classes. The individual RNA fractions isolated from VSV-infected cells or synthesized in vitro were translated in cell-free extracts of wheat germ, and their polypeptide products were compared by sodium dodecyl sulfate-polyacrylamide slab gel electrophoresis. The corresponding in vivo and in vitro RNA fractions qualitatively direct the synthesis of the same viral polypeptides and therefore appear to contain the same mRNA species. By tryptic peptide analysis of their translation products, the in vivo VSV mRNA species have been identified. The 17S RNA, which is compartmentalized on membrane-bound polysomes, codes for a protein of molecular weight 63,000 (P-63) which is most probably a nonglycosylated form of the viral glycoprotein, G. Of the viral RNA species present in the remaining cytoplasmic supernatant, the 14.5S RNA codes almost exclusively for the N protein, whereas the 12S RNA codes predominantly for both the NS and M proteins of the virion.
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PMID:Translation and identification of the viral mRNA species isolated from subcellular fractions of vesicular stomatitis virus-infected cells. 16 12

Upon infection of Chinese hamster ovary cells (CHO), vesicular stomatitis (VSV) virus synthesizes two membrane proteins (the VSV glycoprotein and the VSV matrix or membrane (M) protein) and three nonmembrane proteins (the VSV nucleocapsid, the viral transcriptase, and an NS protein). We have used the VSV-infected cell as a model system for the study of the site of synthesis of these membrane and nonmembrane proteins. We have isolated VSV mRNA from free polyribosomes, membrane-bound polyribosomes, and the postribosomal supernatant, and identified the individual species of VSV mRNA present in each fraction. The mRNA which encodes the VSV glycoprotein is found exclusively on membrane-bound polyribosomes, while the mRNAs which encode the VSV, M, N, and NS proteins are found in free polyribosomes, in the membrane fraction of the cell, and in the postribosomal supernatant. Our results suggest that the VSV glycoprotein is synthesized exclusively on membrane polyribosomes, while at least some of the M, N, and NS proteins are made on free polyribosomes.
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PMID:Site of synthesis of membrane and nonmembrane proteins of vesicular stomatitis virus. 16 63

Glycoprotein mRNA (G mRNA) of vesicular stomatitis virus is synthesized in the cytosol fraction of infected HeLa cells. Shortly after synthesis, this mRNA associates with 40S ribosomal subunits and subsequently forms 80S monosomes in the cytosol fraction. The bulk of labeled G mRNA is then found in polysomes associated with the membrane, without first appearing in the subunit or monomer pool of the membrane-bound fraction. Inhibition of the initiation of protein synthesis by pactamycin or muconomycin A blocks entry of newly synthesized G m RNA into membrane-bound polysomes. Under these circumstances, labeled G mRNA accumulates into the cytosol. Inhibition of the elongation of protein synthesis by cucloheximide, however, allows entry of 60 percent of newly synthesized G mRNA into membrane-bound polysomes. Furthermore, prelabeled G mRNA associated with membrane-bound polysomes is released from the membrane fraction in vivo by pactamycin or mucomycon A and in vitro by 1mM puromycin - 0.5 M KCI. This release is not due to nonspecific effects of the drugs. These results demonstrate that association of G mRNA with membrane-bound polysomes is dependent upon polysome formation and initiation of protein synthesis. Therefore, direct association of the 3' end of G mRNA with the membrane does not appear to be the initial event in the formation of membrane-bound polysomes.
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PMID:Studies on the mechanism for entry of vesicular stomatitis virus glycoprotein G mRNA into membrane-bound polyribosome complexes. 19 7

The interaction of the polyene antibiotic filipin with membrane-bound cholesterol in vesicular stomatitis (VS), influenza, and Rauscher leukemia virions was studied. Exposure of virions to filipin resulted in a series of depressions and ridges in the envelope of VS virions, with a periodicity of 15 to 20 nm perpendicular to the long axis of the particle; similar morphological alterations were observed in negatively stained preparations, in thin-sectioned virions, and in protease-treated virions that lack surface glycoproteins. This morphological effect was specific for filipin, since the envelopes of VS virions that had been treated with another polyene antibiotic, amphotericin B, exhibited markedly different morphology. Morphological alterations induced by filipin in influenza and Rauscher leukemia virions differed from those seen in VS virions. The infectivity of filipin-treated VS virions was reduced up to 500-fold, whereas influenza virions were resistant to filipin treatment. Incorporation of filipin into the virions was demonstrated, and no release of either lipids or proteins from virions was detected after filipin treatment. A stoichiometry of approximately 1 mol of bound filipin per mol of cholesterol was found in both intact and protease-treated VS virions. The equilibrium dissociation constant for filipin-cholesterol interaction was approximately 74-fold larger in intact than in protease-treated VS virions. The initial rate of association of filipin with cholesterol in intact virions was slower than that in protease-treated particles. The fluidity of lipids in VS viral membranes, as probed by a stearic acid derivative spin label, was markedly reduced when either intact or protease-treated virions were treated with filipin.
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PMID:Effects of filipin on the structure and biological activity of enveloped viruses. 20 81

The glycoprotein (G) of vesicular stomatitis virus (VSV) is synthesized on membrane-bound polyribosomes. Approximately 30 min after its synthesis, it reaches the surface plasma membrane where it is incorporated into budding virus. The first part of this paper focuses on the 2 intracellular, membrane-bound, glycosylated forms of the glycoprotein which are intermediates in its biogenesis. All glycosylation and processing is completed in the smooth microsome fraction before the protein reaches the surface. Next, we turn to the mechanism by which G is synthesized on membrane-bound polyribosomes. All of the G mRNA is bound to membranes, and studies with puromycin suggest that this attachment of G mRNA is mediated by the nascent glycoprotein chain. After its synthesis G is a transmembrane protein with about 30 amino acids at the carboxyl terminus remaining on the cytoplasmic side of the endoplasmic reticulum. Since 95% of the glycoprotein, containing the carbohydrate residues, is resistant to attack by external proteases, it appears to be within the lumen of the endoplasmic reticulum or embedded within the lipid bilayer. Finally, we show that synthesis, glycosylation, and proper asymmetric insertion of G into the ER can be achieved in cell-free extracts. Both glycosylation of G and proper insertion into the ER membrane in this cell-free system require concomitant protein synthesis.
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PMID:Membrane assembly: synthesis and intracellular processing of the vesicular stomatitis viral glycoprotein. 21 48

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

I studied the glycosylation in vivo of a viral envelope protein, the glycoprotein of vesicular stomatitis virus (VSV), by pulse labelling of virus-infected HeLa cells with 3H-labelled monosaccharides (mannose, glucosamine). Radioactivity was incorporated into the fraction of membrane-bound polyribosomes, although metabolic conversion of [3H]-mannose into amino acids was negligible. Dissociation of bound polyribosomes revealed that the radioactively co-purified with the peptidyl-tRNA. The nascent peptides were released by alkaline hydrolysis, immunoprecipitated and analysed by polyacrylamide-gel electrophoresis. It is apparent from the size distribution of the [3H]mannose-labelled nascent chains that attachment of carbohydrate starts when approximately half of the amino acid sequence of the viral glycoprotein has been synthesized.
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PMID:Transfer of carbohydrates on to nascent glycoprotein of vesicular stomatitis virus. 22 58

We mapped the in vivo phosphorylation sites for the matrix (M) protein of the Orsay and San Juan strains of vesicular stomatitis virus, Indiana serotype, using limited proteolysis and phosphoamino acid analysis. M protein was solubilized from 32P-labeled virions by using detergent and high-salt conditions, then treated with either trypsin or Staphylococcus aureus V8 protease, and analyzed by polyacrylamide gel electrophoresis and autoradiography to determine which fragments contained phosphate residues. The M protein fragment extending from amino acid 20 to the carboxy terminus contained approximately 70% of the control 32P label, while the fragment extending from amino acid 35 to the carboxy terminus had only trace amounts of label. These data indicate that the major phosphorylation site was between amino acids 20 and 34 in the Orsay strain M protein. Phosphoamino acid analysis of M protein by thin-layer electrophoresis showed the presence of phosphothreonine and phosphoserine and that phosphothreonine continued to be released after prolonged vapor-phase acid hydrolysis. These data identify Thr-31 as the primary in vivo phosphate acceptor for M protein of the Orsay strain of vesicular stomatitis virus. The San Juan strain M protein has serine at position 32, which may also be an important phosphate acceptor. In addition, phosphorylation at Ser-2, -3, or -17 occurs to a greater extent in the San Juan strain M protein than in the Orsay strain M protein. The subcellular distribution of phosphorylated M protein was investigated to determine a probable intracellular site(s) of phosphorylation. Phosphorylated M protein was associated primarily with cellular membranes, suggesting phosphorylation by a membrane-associated kinase. Virion M protein was phosphorylated to a greater extent than membrane-bound M protein, indicating that M protein phosphorylation occurs at a late stage in virus assembly. Phosphorylation of wild-type and temperature-sensitive mutant M protein was studied in vivo at the nonpermissive temperature. The data show that phosphorylated M protein was detected only in wild-type virus-infected cells and virions, suggesting that association with nucleocapsids may be required for M protein phosphorylation or that misfolding of mutant M protein at the nonpermissive temperature prevents phosphorylation.
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PMID:Sites of in vivo phosphorylation of vesicular stomatitis virus matrix protein. 132 2

The glycoside digitonin was used to selectively permeabilize the plasma membrane exposing functionally and morphologically intact ER and Golgi compartments. Permeabilized cells efficiently transported vesicular stomatitis virus glycoprotein (VSV-G) through sealed, membrane-bound compartments in an ATP and cytosol dependent fashion. Transport was vectorial. VSV-G protein was first transported to punctate structures which colocalized with p58 (a putative marker for peripheral punctate pre-Golgi intermediates and the cis-Golgi network) before delivery to the medial Golgi compartments containing alpha-1,2-mannosidase II and processing of VSV-G to endoglycosidase H resistant forms. Exit from the ER was inhibited by an antibody recognizing the carboxyl-terminus of VSV-G. In contrast, VSV-G protein colocalized with p58 in the absence of Ca2+ or the presence of an antibody which inhibits the transport component NSF (SEC18). These studies demonstrate that digitonin permeabilized cells can be used to efficiently reconstitute the early secretory pathway in vitro, allowing a direct comparison of the morphological and biochemical events involved in vesicular tafficking, and identifying a key role for the p58 containing compartment in ER to Golgi transport.
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PMID:Morphological analysis of protein transport from the ER to Golgi membranes in digitonin-permeabilized cells: role of the P58 containing compartment. 144 90

Large polylactosaminoglycans have only been observed linked to membrane proteins. To determine if membrane anchoring of a secretory protein might lead to the addition of polylactosaminoglycan, we have examined the carbohydrate structure on a membrane-anchored form of human chorionic gonadotropin-alpha subunit. This protein was generated by fusing the DNA encoding the human chorionic gonadotropin-alpha subunit to the DNA encoding the membrane-spanning and cytoplasmic domains of the vesicular stomatitis virus glycoprotein. DNAs encoding this hybrid form and the secretory form of human chorionic gonadotropin-alpha were expressed in monkey COS-1 cells using an SV40-based vector. We show here that the parent secretory glycoprotein contains typical Asn-linked complex-type oligosaccharides while the membrane-bound form contains large, heterogenous polylactosaminoglycans. We conclude that membrane anchoring increases the accessibility of the N-linked glycans to the enzymes involved in polylactosamine addition. The inhibitor 1-deoxymannojirimycin blocks addition of the polylactosaminoglycan.
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PMID:A membrane-anchored form but not the secretory form of human chorionic gonadotropin-alpha chain acquires polylactosaminoglycan. 245 68


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