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)

Full-length cDNA copies of mRNAs coding for the matrix (M) proteins of vesicular stomatitis virus and its mutant tsO23(III) were cloned in pBSM13- (BlueScribe). The authenticity of these clones was demonstrated by restriction enzyme mapping, DNA sequencing, and in vitro transcription and translation to identify the two M proteins by Western immunoblotting with epitope-specific monoclonal antibodies. Site-directed mutants were constructed by primer extension of synthetic oligodeoxynucleotides with one or two nucleotide changes to alter the glycine at amino acid 21 of the wild-type (wt) M gene to glutamic acid, alanine, or proline. Similarly, a revertant was created in the M gene of mutant tsO23 by a Glu-21----Gly substitution. A series of wt- and mutant-M-gene chimeras was also constructed to create mutant and revertant clones with Leu----Phe and His----Tyr alterations at amino acids 111 and 227, respectively. We then moved the wt and tsO23 M genes and their site-specific mutants and chimeras cloned in pBSM13- into the eucaryotic expression vector pTF7 directed by the T7 bacteriophage RNA polymerase of the vaccinia virus recombinant vTF1-6,2. Western blot analysis of the M proteins transiently expressed in CV-1 cells by plasmids carrying M genes altered at amino acid 21 revealed that the critical antigenic determinant (epitope 1) is expressed only by the Gly-21 M protein and not by Glu-21, Ala-21, or Pro-21 M proteins. Of particular interest is an apparent conformational change, evidenced by slightly but significantly retarded electrophoretic migration, in plasmid-expressed M proteins with amino acids substituted for glycine at position 21. The glutamic acid at position 21 of tsO23 is not responsible for its temperature-sensitive phenotype, because a tsO23 revertant plasmid with glycine substituted at position 21 fails to rescue tsO23 virus in cells infected at the restrictive temperature; conversely, plasmids expressing wt M protein with substitutions of glutamic acid, alanine, or proline at position 21 are just as effective in marker rescue of tsO23 as is the Gly-21 wt M protein. Marker rescue experiments with wt- and mutant-M-gene chimeras support the hypothesis of K. Morita, R. Vanderoef, and J. Lenard (J. Virol. 61:256-263, 1987) that the temperature-sensitive phenotype of tsO23 is due to a phenylalanine substituted for leucine at amino acid 111, rather than the His-227----Tyr substitution or the Gly-21----Glu substitution, which independently accounts for the loss of epitope 1 in the mutant M protein of tsO23.(ABSTRACT TRUNCATED AT 400 WORDS)
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PMID:Site-specific mutations in vectors that express antigenic and temperature-sensitive phenotypes of the M gene of vesicular stomatitis virus. 245 88

Human immunodeficiency virus (HIV) infection was studied by means of CD4-expressing human-murine T-cell hybrids, containing a variable amount of human chromosomes. Fusion of the HPRT- murine cell line BW5147 with human T-cell acute lymphoblastic leukemia or normal human blood cells resulted in a panel of human-murine T-cell hybrids. For this study, we used four hybrids containing all or several human chromosomes, which all expressed the CD4 antigen, as assessed by different anti-CD4 monoclonal antibodies (e.g., OKT4A, Leu-3a, and MT151) and, in addition, a variable number of other human T-cell antigens. For infection, HTLV-IIIB-infected H9 cells, pretreated with mitomycin C, and cell-free concentrated supernatants from these cells were used. In cells of inoculated cultures of the CD4+ T-cell hybrids, no viral antigen could be demonstrated. Culture supernatants of inoculated hybrids, except for an initial rise due to the virus inoculum, never showed reverse transcriptase activity above background. Cocultivation of these cell cultures with H9 cells did not result in detectable virus replication. Cocultivation of CD4-expressing hybrid cells with HIV-infected cells did not result in syncytium formation. Moreover, these hybrids were resistent to infection with vesicular stomatitis virus (VSV)-HIV pseudotypes. These findings imply that expression of the CD4 antigen on the cell surface is not sufficient for productive infection with HIV. The infectivity block observed in these hybrids seems to occur at the level of virus penetration, presumably at the stage of membrane fusion events.
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PMID:Human immunodeficiency virus infection studied in CD4-expressing human-murine T-cell hybrids. 246 72

The matrix (M) protein of vesicular stomatitis virus serves as an endogenous inhibitor of viral transcription, a function missing or deficient in M proteins of temperature-sensitive (ts) mutants assigned to complementation group III. Previous studies with mutant tsO23(III) and vaccinia virus M-gene expression vectors revealed that the temperature-sensitive phenotype is due to a mutation leading to substitution of phenylalanine for leucine at amino acid III, whereas loss of the major antigenic determinant (epitope 1) of the mutant M protein results from the substitution of glutamic acid for the wild-type amino acid glycine at position 21 (Y. Li, L. Luo, R. M. Snyder, and R. R. Wagner, J. Virol. 62:3729-3737, 1988). We demonstrate here that transcription inhibition activity is restored to rescued tsO23 virus only when the rescuing vaccinia virus recombinant expresses M protein with glycine and not glutamic acid at amino acid 21. These experiments indicate the importance of the conformational integrity of the amino-terminal domain in determining the capacity of the vesicular stomatitis virus M protein to down regulate endogenous transcription.
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PMID:Transcription inhibition site on the M protein of vesicular stomatitis virus located by marker rescue of mutant tsO23(III) with M-gene expression vectors. 254 94

Recombinant interleukin-2 (rIL-2) (NSC# 600664; Hoffmann-La Roche, Inc., Nutley, NJ) was studied in a phase I clinical trial in 33 patients with advanced, measureable cancer of the colon or malignant melanoma, Eastern Cooperative Oncology Group (ECOG) performance status O-1, and no prior chemotherapy or radiotherapy. The goal of the study was to identify a dose and schedule of IL-2 to generate maximal immune modulation with tolerable toxicity. Such a regimen might allow the addition of other treatment modalities and/or prolonged treatment duration in later trials. Each patient received IL-2 as a continuous 24-hour infusion once weekly for 4 weeks and then twice weekly for 4 weeks. Five treatment groups received from 10(3) U/m2 to 3 x 10(7) U/m2 per 24-hour infusion. The maximal tolerated dose was 3 x 10(7) U/m2/d twice weekly. Patients treated twice weekly at 1 x 10(7) and 3 x 10(7) U/m2/d had immune modulation in terms of lymphocytosis, eosinophilia, increased natural killer (NK) activity, and elevated numbers of peripheral blood mononuclear cells expressing CD16, OKT10/Leu-17, and Leu-19 surface markers. Endogenous generation of peripheral blood lymphokine-activated killer (LAK) activity was demonstrated by lysis of NK-resistant Daudi targets, in patients treated at 3 x 10(7) U/m2/d. Biochemical and hematological abnormalities were moderate and reversible. Clinical toxicity included hypotension, myalgia, arthralgia, stomatitis, fever, fatigue, nausea, headache, chills, diarrhea, and oliguria at high doses. Cardiovascular toxicity was tolerable for most patients and reversed after IL-2 was stopped. Two of six melanoma patients at 3 x 10(7) U/m2/d achieved partial responses by the end of the eighth week. This IL-2 schedule appears to produce potentially clinically useful immune enhancement with tolerable toxicity.
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PMID:A phase I clinical trial of recombinant interleukin-2 by periodic 24-hour intravenous infusions. 278 32

We have examined and compared the host-cell-dependent glycosylation of the G glycoprotein of vesicular-stomatitis virus (Hazelhurst strain) and the E1 and E2 glycoproteins of Sindbis virus replicated by baby-hamster kidney, chicken-embryo fibroblast and mouse L929 monolayer cell cultures. The results of endo-beta-N-acetylglucosaminidase H digestion of viral proteins labelled with [3H]mannose or leucine and Pronase-digested glycopeptides labelled with [3H]mannose indicated that both the G protein and the E1 protein contained a similar mixture of endoglycosidase-resistant oligosaccharides of the complex acidic type and less extensively processed endoglycosidase-sensitive oligosaccharides of the neutral or hybrid type, with a relatively greater content of the endoglycosidase-sensitive oligosaccharides for virus replicated in the chicken as against hamster or mouse cells. A large fraction of the G protein and the majority of the E1 proteins from the mammalian host cells contained acidic-type oligosaccharides at both glycosylation sites, whereas most of the G and E1 glycoproteins from the avian host cells and essentially all of the E2 protein from all three host-cell types contained an acidic-type oligosaccharide at one site and neutral- or hybrid-type oligosaccharide at the other site. The relative increase in neutral- and hybrid-type oligosaccharides with five-mannose core structures observed for the G and E1 proteins of virus released from the avian host cells suggested that two specific steps in oligosaccharide processing (mediated by alpha-mannoside II and N-acetylglucosaminyltransferase I) were less efficient at one of the glycosylation sites of the vesicular-stomatitis-virus G protein and Sindbis-virus E1 protein in the avian as against mammalian host cells.
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PMID:Hazelhurst-vesicular-stomatitis-virus G and Sindbis-virus E1 glycoproteins undergo similar host-cell-dependent variation in oligosaccharide processing. 299 31

The conformations of synthetic peptides Lys-Phe-Phe-Phe-Ile-Ile-Gly-Leu-Ile-Ile-Gly-Leu-Phe-OCH3 and Lys(epsilon-palmitoyl)-Phe-Phe-Phe-Ile-Ile-Gly-Leu-Ile-Ile-Gly-Leu-Phe-O CH3, which constitute a part of the membrane-spanning region of the vesicular stomatitis virus G protein, have been studied by circular dichroism (CD) spectroscopy. Secondary structural features are observed for both peptides in trifluoroethanol, methanol, aqueous mixtures of trifluoroethanol and methanol and in a micellar environment. In trifluoroethanol, the CD spectra indicate the presence of a helical conformation, whereas in aqueous mixtures of organic solvents, both helical and beta-conformations are observed. While fatty acid acylation does not directly modulate peptide conformation, it promotes self-association of the acylated peptide and association with micelles. In a micellar environment, the acylated peptide adopts an alpha-helical conformation.
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PMID:Circular dichroism studies on a synthetic peptide corresponding to the membrane-spanning region of vesicular stomatitis virus G protein and its fatty acyl derivative. 302 85

Polymorphonuclear leukocyte (PMN) function was investigated in two patients with glycogen storage disease type IB and neutropenia. Glycogen storage disease type IB was documented by liver biopsy and a normal amount of latent glucose-6-phosphatase activity. Patient A had stomatitis, skin infections, and septicemia; patient B had respiratory infections, periodontitis, and oral candidiasis. Absolute neutrophil counts ranged from 114 to 2580/mm3. Diminished and delayed migration of PMN into a skin "window" occurred in B. Random and directed PMN migration under agarose toward f-Met-Leu-Phe, pepstatin A, and zymosan-activated serum were severely diminished in both patients. At 10(-7) M f-Met-Leu-Phe, mean random and directed migration were 52 and 23% (A, n = 3) and 48 and 13% (B, n = 4) of controls. These results were independent of incubation time and chemoattractant concentration. Patients' PMN had diminished quantitative nitroblue tetrazolium reduction compared to controls. B had a significant defect in PMN bactericidal activity with Escherichia coli with less than 0.2 log killing at 2 h. These results further characterize the defect in PMN migration reported by Beaudet et al. (J Pediatr 97:906, 1980). The finding of other abnormalities of PMN function suggests a metabolic defect in the neutrophil which may be related to the microsomal membrane defect in hepatocytes in glycogen storage disease type IB.
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PMID:Impaired chemotaxis and neutrophil (polymorphonuclear leukocyte) function in glycogenosis type IB. 345 31

9-beta-d-Arabinofuranosyladenine (Ara-A) effectively inhibited the production of infectious vesicular stomatitis virus (VSV) in MDBK cells. Furthermore, inhibition was shown to begin as early as the first 3 hr of infection. Studies employing (3)H-l-leucine indicated that Ara-A did not affect protein synthesis in uninfected cells, although it did cause a marked stimulation of protein synthesis in VSV-infected cells during the log phase of the growth cycle. Puromycin, an inhibitor of protein synthesis, was a more effective viral inhibitor than Ara-A. However, the combination of Ara-A and puromycin was less effective than puromycin alone except when present for long time periods. Short-term labeling experiments with (3)H-uridine demonstrated that Ara-A depressed ribonucleic acid (RNA) synthesis in uninfected cells, whereas periods of stimulation and depression of radioisotope incorporation occurred in infected cells. The results support the notion that Ara-A is incorporated into RNA early during viral replication.
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PMID:Inhibition of vesicular stomatitis virus replication by 9-beta-D-arabinofuranosyladenine. 436 72

Swainsonine, an inhibitor of glycoprotein processing, inhibits the formation of the normal oligosaccharide chain of the G protein of vesicular stomatitis virus. Thus, when vesicular stomatitis virus was grown in baby hamster kidney cells in the presence of swainsonine (15 to 500 ng/ml) and labeled with [2-(3)H]mannose, the oligosaccharide portion of the G protein was completely susceptible to the action of endoglucosaminidase H. However, the normal viral glycoprotein is not susceptible to this enzyme. Various enzymatic treatments and methylation studies of the mannose-labeled oligosaccharides suggest that swainsonine causes the formation of a hybrid-type oligosaccharide having an oligomannosyl core (Man(5)GlcNAc(2)-Asn) characteristic of neutral oligosaccharides plus the branch structure (NeuNAc-Gal-GlcNAc) characteristic of the complex oligosaccharides. A structure for this hybrid oligosaccharide is proposed. Swainsonine had no effect on the incorporation of [(14)C]leucine into viral proteins, nor did it change the number of PFU produced in these cultures. It did, however, slightly decrease the incorporation of [(3)H]glucosamine and increase the incorporation of [(3)H]mannose. Vesicular stomatitis virus raised in the presence of swainsonine bound much more tightly to columns of concanavalin A-Sepharose than did control virus. Swainsonine had to be added within the first 4 or 5 h of virus infection to be effective. Thus, when 100 ng of the alkaloid per ml was added at any time within the first 3 h of infection, essentially all of the glycoprotein was susceptible to digestion by endoglucosaminidase H. However, when swainsonine was added 4 h after the start of infection, 30% of the glycopeptides became resistant to endoglucosaminidase H; at 5 h, 70% were resistant. The effect of swainsonine was reversible since removal of the alkaloid allowed the cells to form the normal complex glycoproteins. However, the time of removal was critical in terms of oligosaccharide structure.
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PMID:Alterations in the structure of the oligosaccharide of vesicular stomatitis virus G protein by swainsonine. 629 70

In a microsome system rendered competent in protein translation by the addition of rabbit reticulocyte lysate, co-translational insertion and glycosylation of N-linked glycoproteins is observed when the appropriate mRNA is supplied. We have utilized this system to examine the ability of acceptor tripeptides of the type Asn-X-Thr/Ser to inhibit co-translational glycosylation. Using endogenous oligosaccharide-lipid as the carbohydrate donor, dog pancreas microsomes efficiently glycosylated N alpha-[3H]Ac-Asn-Leu-Thr-NHCH3 (apparent Km = 100 microM). Glycopeptide formation was essentially complete within 20 min. In the presence of mRNA from vesicular stomatitis virus or chicken ovalbumin, a similar tripeptide, N alpha-Ac-Asn-Leu-Thr-NH2, inhibited co-translational glycosylation. Translocation of the nascent chains was not affected. Thus, in the absence of peptide, all translated G protein was glycosylated and found within the microsomes, whereas in the presence of the peptide a mixture of glycosylated and nonglycosylated G protein was sequestered. Inhibition of nascent chain glycosylation was competitive and not merely the result of oligosaccharide lipid depletion, because preincubation of the microsomes with the peptide followed by its removal did not affect subsequent glycosylation of ovalbumin or G protein. Six derivatives of Asn-Leu-Thr-NH2, three of which were acceptors and three of which were not, were tested for their ability to inhibit co-translational glycosylation. The three acceptor peptides, N alpha-Ac-Asn-Leu-Thr-NH2, N alpha-Oc-Asn-Leu-Thr-NH2, and N alpha-Bz-Asn-Leu-Thr-NH2, effectively inhibited nascent chain glycosylation. In contrast, the three nonacceptors, N alpha-Ac-Gln-Leu-Thr-NH2, N alpha-Ac-Asn(N beta-Me)-Leu-Thr-NH2, and Asn-Leu-Thr-NH2, had no effect. Taken together, these data indicate that the inhibition of co-translational glycosylation by a peptide is dependent on its ability to compete for the active site of the oligosaccharyl transferase.
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PMID:Substrate recognition by oligosaccharyl transferase. Inhibition of co-translational glycosylation by acceptor peptides. 668 31


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