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)

Secretory proteins migrate from the rough endoplasmic reticulum (ER) to the Golgi complex at different rates. Selective retention of specific proteins to rough-ER membrane constituents could explain this phenomenon. We have permeabilized HepG2 cells with low concentrations of saponin. Release of newly synthesized proteins was studied after brief labelling in the presence of [35S]methionine. The efflux of several secretory proteins was studied at various saponin concentrations; a 2-fold higher saponin concentration was required to release transferrin compared with that required to release albumin and orosomucoid. Glucosidase II, a soluble resident protein of the ER, is released at the same saponin concentration as albumin. Saponin did not destroy the membrane skeleton structure; at the concentrations used, the integral membrane protein G of vesicular-stomatitis virus remained fully associated with the cells.
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PMID:Release of soluble resident as well as secretory proteins from HepG2 cells by partial permeabilization of rough-endoplasmic-reticulum membranes. 253 21

We have isolated a vesicular stomatitis virus (VSV)-specific CD4+ CD8- murine T-cell clone. This clone proliferates only in response to VSV and lyses infected tumor cells bearing class II major histocompatibility antigens in short-term chromium release assays. In addition, the cell has VSV antigens on its surface and is capable of killing uninfected tumor cells without major histocompatibility antigen restriction in a 2-day assay. This latter cytolytic activity is eliminated by anti-VSV antibody, indicating that its lytic activity is provided by the virus. [35S]methionine labeling and immunoprecipitation experiments demonstrated that viral protein translation is initiated after incubation of the clone with a tumor target cell, defining this as the mechanism of its cytolytic activity.
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PMID:Trojan horse lymphocytes: a vesicular stomatitis virus-specific T-cell clone lyses target cells by carrying virus. 255 Jun 62

Other workers have reported that vesicular stomatitis virus makes aberrantly long polyadenylic acid [poly(A)] tracts in the presence of S-adenosylhomocysteine (S-Ado-Hcy). In the work reported in this paper, the effects of various analogues of S-adenosylmethionine (S-Ado-Met) and ATP on polyadenylation in an in vitro transcription system were examined to determine whether S-Ado-Hcy exerted its effect on polyadenylation due to its relationship to S-Ado-Met or to ATP. It appeared that compounds which affected polyadenylation were those which were closely related to S-Ado-Met and that had the same L-aminoacyl side chain [(COOH)-CH(NH)2-CH2-CH2-]; the nature of the substituent at the -S+(CH3)- position of S-Ado-Met was less important. These analogues appeared to compete with S-Ado-Met for a binding site(s). These data support a model whereby compounds binding at an S-Ado-Met-binding site may have allosteric effects by causing or preventing conformational changes which are involved in polyadenylation reactions, perhaps by affecting the rate of polyadenylation or of termination.
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PMID:Effect of analogues of S-adenosylmethionine on in vitro polyadenylation by vesicular stomatitis virus. 256 41

We have developed a highly efficient in vitro-transport assay that couples translocation across the ER membrane and transport to the Golgi complex using the secreted pheromone alpha-factor as a marker protein. Radiolabeled prepro-alpha-factor of high specific radioactivity is obtained by in vitro-translating this protein in a yeast lysate. Prepro-alpha-factor synthesized in vitro is then translocated directly into microsomes or the ER of permeabilized yeast cells. Conversion of the 26-kDa ER form of pro-alpha-factor to the high molecular weight Golgi form is dependent on the presence of ATP and soluble and membrane-bound factors. Differential centrifugation and fractionation on a sucrose gradient have shown that the ER and Golgi forms of alpha-factor are enriched in separate compartments after the transport reaction. These and other findings (see Ruohola et al., 1988, for a more complete discussion) indicate that conversion to the high molecular weight form of alpha-factor is the result of authentic intercompartmental transport. Permeabilized mammalian cells have been used to reconstitute transport from the ER to the Golgi complex. In these systems (Becker et al., 1987; Simons and Virta, 1987), a viral membrane glycoprotein protein (vesicular stomatitis virus G protein) is used as the marker protein. This protein is radiolabeled with [35S]methionine during virus infection, either before or after the cells are permeabilized. Radiolabeled G protein, residing in the ER, is then transported to the Golgi complex in the presence of an ATP-regenerating system. In the mammalian system the donor and acceptor compartments are retained within the permeabilized cells (Simons and Virta, 1987); however, on occasion the addition of an exogenous acceptor compartment is required (Beckers et al., 1987). The assay we developed (Ruohola et al., 1988) differs from the mammalian assay (Beckers et al., 1987) in that we introduce radiolabeled marker protein into the ER in vitro during translocation rather than during virus infection. In addition, in our assay the acceptor Golgi compartment is always provided exogenously to the permeabilized cells. Therefore, if acceptor membranes are present in the PYC, they are not utilized. Because the permeabilized cells and the S3 fraction are prepared differently, the conditions used to prepare the cells may lead to inactivation or loss of the acceptor compartment. The in vitro assay will enable us to purify components involved in transporting proteins from the lumen of the ER to the Golgi complex. Antibody prepared to purified components can be used to clone the genes that code for these proteins.(ABSTRACT TRUNCATED AT 400 WORDS)
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PMID:Reconstitution of transport from the ER to the Golgi complex in yeast using microsomes and permeabilized yeast cells. 267 24

Various adenosine analogues, i.e. (S)-9-(2,3-dihydroxypropyl)adenine, (RS)-3-adenin-9-yl-2-hydroxypropanoic acid, carbocyclic 3-deazaadenosine and neplanocin A, which have been previously recognized as specific inhibitors of S-adenosyl-L-homocysteine (SAH) hydrolase, gained a marked increase in their cytostatic activity (against tumor cells) and antiviral activity (against vaccinia and vesicular stomatitis virus) in the presence of L-homocysteine (10(-3) M). Homocysteine did not increase the cytostatic or antiviral activity of those compounds (i.e. tubercidin, ribavirin, acyclovir or vidarabine) that do not achieve their biological activity via SAH hydrolase inhibition. The increased antiviral activity following addition of homocysteine was observed only with those viruses (i.e. vaccinia and vesicular stomatitis virus) that belong to the activity spectrum of SAH hydrolase inhibitors [Biochem Pharmacol 36: 2567-2575, 1987], and only in those cells in which the SAH hydrolase inhibitors are normally active. The enhancing effect of homocysteine on the cytostatic and antiviral activity of the SAH hydrolase inhibitors could not be attributed to a non-specific increase in the cytotoxicity of the compounds, as their effects on host cell macromolecule (DNA, RNA, protein) synthesis was not markedly altered in the presence of homocysteine. Most likely, homocysteine exerted its potentiating effect on the activity of the SAH hydrolase inhibitors through an increase in the intracellular levels of SAH, which is known to act as a product inhibitor of S-adenosyl-L-methionine (SAM)-dependent transmethylation reactions.
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PMID:Homocysteine potentiates the antiviral and cytostatic activity of those nucleoside analogues that are targeted at S-adenosylhomocysteine hydrolase. 273 35

Infection of L929 murine cells with vesicular stomatitis virus (VSV) results in inhibition of host protein synthesis and appearance of membrane alterations at a time when cells are still actively engaged in viral protein synthesis. VSV temperature-sensitive (ts) mutants have been used to explore the role(s) played by the virus-coded proteins in the genesis of these effects. Cells were infected with each of five ts mutants representing the known complementation groups of VSV Indiana serotype, and incubated at permissive (32 degrees C) and non-permissive temperatures (39 degrees C). Protein synthesis in the presence and absence of Hygromycin B (Hyg. B) was analyzed during virus infection via incorporation of 35S-methionine in acid-precipitable material and SDS-polyacrylamide gel electrophoresis. Data indicate that mutants belonging to groups I (L protein), II (NS protein) and IV (N protein) do not inhibit host protein synthesis and do not induce any membrane changes when grown at the non-permissive temperature. Mutants of group III (M protein) and V (G protein), instead, do inhibit cell protein synthesis and induce membrane changes also when grown at the non-permissive temperature; this suggests that these effects do not correlate with the biological activity of these proteins and their interaction with the cellular membrane. On the other hand, mutants exhibiting defective steps of nucleocapsid replication are apparently unable to induce these effects once more suggesting that virus replication per se is essential, as also indirectly shown by experiments employing cycloheximide to mimic shut-off.
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PMID:L929 cells infected with temperature sensitive mutants of vesicular stomatitis virus: virus replication is necessary for induction of changes in membrane permeability. 282 8

When purified, [35S]methionine-labeled vesicular stomatitis virus (VSV) was exposed to ultraviolet light, an irradiation-induced change in the viral proteins was detected by SDS-polyacrylamide gel electrophoresis and immunoblotting. With dose of uv irradiation in the same range as that required to inactivate VSV leader RNA, a loss occurred in the bands corresponding to the L and NS proteins concomitant with the appearance of several new bands of radioactivity throughout the gel. This alteration of viral proteins correlated with the loss of ability of the virus to inhibit host macromolecular synthesis. In light of these results, the role that has been ascribed to the VSV leader RNA in VSV-mediated host shut-off needs to be reevaluated.
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PMID:Alteration of vesicular stomatitis virus L and NS proteins by uv irradiation: implications for the mechanism of host cell shut-off. 283 68

A mutant (MO-5) resistant to monensin (an ionophoric antibiotic) derived from the mouse Balb/3T3 cell line, was a poor host for vesicular stomatitis virus (VSV) or semliki forest virus (SFV) multiplication. The yield of VSV particles in MO-5 is one 100-fold reduced as is VSV-dependent RNA synthesis. In contrast to a pH-remedial mutant, the abortive production of infectious VSV particles in MO-5 cells was not restored by low pH treatment. The pH values in the endosome and the lysosome of MO-5 cells were 5.2 and 5.4, respectively, values that were comparable to the pH value in Balb/3T3 cells. Assays with [3H]uridine-labeled VSV indicated similar binding of VSV in MO-5: percoll gradient centrifugation analysis of [35S]methionine-labeled VSV-infected Balb/3T3 showed accumulation of VSV in the lysosome fraction 20 min after VSV infection, whereas VSV can be found mainly in endosome/Golgi fraction of MO-5 cells after 40 to 60 min on the percoll gradients. Degradation of [35S]methionine-labeled VSV was observed at a significant rate in Balb/3T3 cells, but not in MO-5 cells. The monensin-resistant somatic cell may thus provide a genetic route to study the mechanism of endocytosis or transport of enveloped viruses.
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PMID:Monensin-resistant mouse Balb/3T3 cell mutant with aberrant penetration of vesicular stomatitis virus. 286 Dec 7

We studied the intracellular transport of secretory and membrane proteins in the human hepatoma cell line HepG-2 infected with vesicular stomatitis virus. Cells were pulse-labeled in the presence of [35S]methionine and chased in the presence of the lysosomotropic agent primaquine. At a concentration of 0.3 mM primaquine effectively inhibited the secretion of albumin and, to a lesser extent, that of orosomucoid and transferrin. The drug also prevented the budding of virus particles at the cell surface. The intracellular transport to the Golgi complex of the membrane protein VSV-G was not affected by primaquine as it acquires resistance to endo-beta-N-acetylglucosaminidase H at the same rate as in control cells. Addition of primaquine at various times after the initiation of the chase period indicates that the effect of primaquine occurs just before secretion. In confirmation of the biochemical data, immunocytochemical localization of albumin in cells treated with NH4Cl demonstrated that albumin accumulated in vesicles at the trans side of the Golgi complex. The effect of primaquine on secretion was also compared with its effect on receptor recycling. The dose-response characteristics of the effect of primaquine on receptor recycling are identical to those of the effects on protein secretion and virus budding. These results indicate that both processes involve the same transport mechanism, and/or that they occur via at least one identical intracellular compartment.
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PMID:Effect of lysosomotropic amines on the secretory pathway and on the recycling of the asialoglycoprotein receptor in human hepatoma cells. 299 1

The association of poliovirus metabolism with the cytoskeleton was investigated. Infected cells were extracted by using the nonionic detergent Triton X-100 in the physiological cytoskeleton buffer. The skeletal framework obtained was examined by transmission electron microscopy of resinless sections. The fibers of the framework were grossly distorted in infected cells. No virions or procapsids were seen but many virus-specific spheroidal bodies were associated with the framework. They had a diameter of 40 to 70 nm, were characterized by a dense core and a translucent periphery, and occurred in strings, often near the remnants of flattened vesicles. These spheres may correspond to virus-synthesizing bodies. The metabolism of poliovirus RNA was shown to be associated with the skeletal framework by pulse-labeling cells with [3H]uridine and measuring the RNA retained on the framework. 20S double-stranded RNA, a form of poliovirus RNA found only in the replication complex, was attached to the skeleton throughout a 60-min pulse-label. 35S single-stranded viral RNA, a form found in virions, in polyribosomes, and in the replication complex, appeared first on the framework but after a few minutes was also found in the soluble cytoplasmic phase, encapsidated in virions. In contrast to viral RNA, viral proteins exhibited a varied association with the skeletal framework. Viral proteins were pulse-labeled with [35S]methionine and chased with unlabeled methionine. Although all of the virus-specific proteins were found, to some extent, in the skeletal fraction, the derivatives of P2 (P2-X and P2-5) and a derivative of P3 (P3-2) showed a preferential association with the skeletal framework. Virions and procapsids, on the other hand, were not associated with the cytoskeleton; both they and their component proteins (P1-VP0, P1-VP1, P1-VP2, and P1-VP3) were found dominantly in the soluble cytoplasmic phase. The pathway of poliovirus assembly can be inferred from the above data. It is different from that found previously for the enveloped vesicular stomatitis virus and may be representative of encapsidated cytoplasmic virus assembly.
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PMID:Poliovirus metabolism and the cytoskeletal framework: detergent extraction and resinless section electron microscopy. 299 75


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