Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts: Gene/Protein Disease Symptom Drug Enzyme Compound   Target Concepts: 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 nucleotide sequence of the L gene of Marburg virus, strain Musoke, has been determined. The L gene has a single long open reading frame encoding a polypeptide of 2330 amino acids (MW 267,175) that represents the viral RNA-dependent RNA polymerase. The putative transcription start signal (3'CUACCUAUAAUU 5') and the termination signal (3' UAAUUCUUUUU 5') of the gene could be identified. Computer-assisted comparison of the L protein with L proteins of other nonsegmented negative-stranded RNA viruses (Paramyxoviridae: Sendai virus, Newcastle disease virus, human parainfluenza 3 virus, measles virus, human respiratory syncytial virus; Rhabdoviridae: vesicular stomatitis virus, rabies virus) revealed significant homologies primarily in the N-terminal half of the proteins. We have identified three common conserved boxes (A, B, and C) among filo-, paramyxo-, and rhabdovirus L proteins, which are probably involved in the polymerase function. The L proteins can be divided into an N-terminal half, which seems to accommodate the common enzymatic sites, and a C-terminal half carrying virus specific peculiarities. The data presented here suggest a common evolutionary history for all nonsegmented negative-stranded RNA viruses and show that filoviruses are more closely related to paramyxo- than to rhabdoviruses.
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PMID:The nucleotide sequence of the L gene of Marburg virus, a filovirus: homologies with paramyxoviruses and rhabdoviruses. 154 52

tsG16(l), a temperature-sensitive mutant of vesicular stomatitis virus, in vitro has at least three phenotypic differences from its parental wild-type (wt) virus due to mutation of the L gene. It was not known whether (i) the temperature-sensitivity of the transcriptase, (ii) the aberrant polyadenylation phenotype, and (iii) the extent of increased polyadenylation in response to S-adenosylhomocysteine (SAH) were associated with a single mutation. Spontaneous partial revertants were selected from tsG16(I) on the basis of the ability to form plaques at 34.7 degrees (35G16 revertants) or from 35G16 revertants on the basis of the ability to form plaques at 37 degrees (37G16 revertants). All six 35G16 revertants had fully (five) or partially (one) recovered the wt polyadenylation phenotype and the former five had also fully recovered the wt polyadenylation response to SAH. This suggested that a single mutation in tsG16(I) was probably associated with both of these phenotypes and also probably conferred the inability to grow at 34.7 degrees. None of the 35G16 revertants regained the wt phenotype for thermosensitivity of the transcriptase, although both of the 37G16 revertants did. This suggested that in vitro temperature-sensitivity of transcription by tsG16(I) might be due to a mutation different than the one affecting polyadenylation in the absence or presence of SAH.
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PMID:Revertants of a mutant of vesicular stomatitis virus which has an aberrant polyadenylation activity and a temperature-sensitive transcriptase. 168 26

Nonsegmented negative strand RNA viruses comprise major human and animal pathogens in nature. This class of viruses is ubiquitous and infects vertebrates, invertebrates, and plants. Our laboratory has been working on the gene expression of two prototype nonsegmented negative strand RNA viruses, vesicular stomatitis virus (a rhabdovirus) and human parainfluenza virus 3 (a paramyxovirus). An RNA-dependent RNA polymerase (L and P protein) is packaged within the virion which faithfully copies the genome RNA in vitro and in vivo; this enzyme complex, in association with the nucleocapsid protein (N), is also involved in the replication process. In this review, we have presented up-to-date information of the structure and function of the RNA polymerases of these two viruses, the mechanisms of transcription and replication, and the role of host proteins in the life-cycle of the viruses. These detailed studies have led us to a better understanding of the roles of viral and cellular proteins in the viral gene expression.
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PMID:Gene expression of nonsegmented negative strand RNA viruses. 177 Nov 77

To study the biological function of the NS protein of vesicular stomatitis virus (VSV), we prepared 21 species of synthetic oligopeptides with 11-21 amino acid residues, corresponding to every portion of the amino acid sequence of NS protein (Indiana serotype), and tested their effects on the VS virion (VSV) transcriptase activity in vitro. Only one peptide affected the virion-associated transcriptase activity of VSV Indiana, by reducing the incorporation of [3H]GMP into acid-insoluble fraction (IC50 = 26 microM). This peptide, the amino acid sequence of which corresponded to the carboxy (C)-terminal region of NS protein, also inhibited the New Jersey serotype virus transcriptase activity, as expected from a high degree of homology found between the amino acid sequences of the C-terminal regions of NS protein of both serotype viruses. Electrophoretic analysis on acrylamide gels of RNA transcripts revealed that the inhibitory synthetic peptide decreased the frequency of the initiation of transcription with no apparent effect on the chain-elongation process of viral transcription. As expected from its highly conserved amino acid sequence, these results suggest that the C-terminal domain of VSV NS protein is involved in initiating viral RNA synthesis.
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PMID:Vesicular stomatitis virion-associated transcriptase activity was suppressed in vitro by a synthetic 21 amino acid oligopeptide prepared to mimic the carboxy-terminus of NS protein. 216 48

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

Mouse L-929 cells (L cells), human oligodendroglioma cells, and rat glioma cells were persistently infected with vesicular stomatitis virus (VSV) mutant tsG31 and maintained for at least 4 years at 37 degrees C. The striking observation in this study was that there is a marked difference in neurovirulence among the persistent infections (PIs) derived from the three cell lines. tsG31 VSV derived from persistently infected L cells and oligodendroglioma cells remained highly virulent as assayed by intracerebral (i.c.) inoculation into 3-week-old Swiss mice. In contrast, tsG31 VSV isolated from glioma cells lost neurovirulence by passage 20. Persistently infected glioma cells were carried through more than 180 passages without reemergence of neurovirulent virus. Importantly, glioma PI virus neurovirulence was restored quickly by i.c. passage in mice and more slowly by passage through normal L cells. In contrast, the neurovirulence of L-cell PI virus was enhanced by i.c. passage in mice and slowly reduced by passage through normal glioma cells. Furthermore, no alteration in neurovirulence was observed in the case of oligodendroglioma PI virus. Although the mechanism(s) underlying the loss of virulence in glioma cells is unclear, our studies suggest that either strict temperature sensitivity or the presence of a heat-labile transcriptase or both play a major role in this phenomenon.
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PMID:Persistent infection of a temperature-sensitive G31 vesicular stomatitis virus mutant in neural and nonneural cells: biological and virological characteristics. 242 95

The vesicular stomatitis virus thermolabile mutant tl17 contains multiple lesions. The RNA-dependent RNA polymerase is temperature sensitive during primary transcription. The glycoprotein develops Endo H sensitivity more slowly at the nonpermissive temperature. Maturation or incorporation of the glycoprotein into progeny virions is also reduced. When virions of tl17 made at the permissive temperature are incubated in buffered medium at 39 degrees, their glycoprotein is cleaved, resulting in a product that resembles soluble glycoprotein. Compared to another glycoprotein mutant, ts 045, the glycoprotein of tl17 is only partially degraded to soluble G intracellularly and is more thermolabile. These properties of tl17 make it potentially useful for studies on glycoprotein synthesis, processing, and transport as well as for studies on pseudotype formation and viral maturation.
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PMID:Multiple thermolabile and temperature-sensitive lesions in mutant tl17 of vesicular stomatitis virus. 247 64

The bee venom peptide melittin activated the virion transcriptase activity of three vesiculoviruses with preservation of virion structure. The kinetics of RNA synthesis were similar to those observed with purified transcribing nucleoprotein (TNP) preparations. Six temperature-sensitive host range (tdCE) mutants of Chandipura virus displayed 1.7- to 5.5-fold greater efficiencies of transcription at 39 degrees with melittin-permeabilized virions in comparison with TNP preparations. Comparative study of other host range mutants (tdCE3) and tsB1) of vesicular stomatitis virus (VSV) New Jersey and a thermosensitive polymerase mutant (tsG114) of VSV Indiana suggested that the enhanced transcription at 39 degrees associated with melittin-activated tdCE mutants was due to the retention of host factors in the virions.
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PMID:Effect of melittin on transcription by vesiculovirus mutant and wild-type viruses. 282 6

In a continuation of previous efforts to study the modified ATP requirements for RNA synthesis by poIR mutants of vesicular stomatitis virus (VSV), we have used a novel reconstitution assay to show that it is the template moiety of the mutants, not the polymerase proteins, which governs both the increased utilization of the ATP analog, beta, gamma-imido ATP (AMP-PMP), and the loss of a positive cooperativity-like response to varying ATP concentrations. Assays utilized uv-irradiated virus as a source of polymerase proteins and purified N-RNA as templates. Homologous and heterologous transcriptase reactions were carried out with wild-type (wt) virus and each of the two independently isolated poIR mutants. We show that in the presence of wt N-RNA template, substitution of AMP-PNP for ATP resulted in only approximately 5% of control RNA synthesis regardless of which source of polymerase was used. Furthermore, all reactions containing wt N-RNA template responded to varying ATP concentrations with a concave, upward-shaped Lineweaver-Burke plot generally indicative of positive cooperativity effects. In contrast, all reactions which utilized N-RNA templates from the poIR mutants showed an increased utilization of AMP-PNP (greater than 20%) and a more characteristic Michaelis-Menten response to changing ATP concentrations. These findings strongly support the notion that the template-associated nucleocapsid protein modulates the utilization of an ATP site which is directly or indirectly involved in VSV RNA synthesis.
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PMID:Altered ATP utilization by the poIR mutants of vesicular stomatitis virus maps to the N-RNA template. 284 22

The roles of the L and NS polypeptides in transcription by vesicular stomatitis virus New Jersey were studied using a mutant, tsE1, which contains a temperature-sensitive transcriptase and an altered NS polypeptide, both phenotypic changes being the consequence of the ts mutation. Mutant tsE1, its revertant (tsE1/R1) and the wild-type virus were dissociated into sub-viral fractions and, after reconstitution of these fractions in all combinations, the transcriptase was assayed in vitro at the permissive (31 degrees C) and restrictive (39 degrees C) temperatures. Reconstitution of the pellet fractions (containing polypeptide N complexed with the virion RNA) and the supernatant fractions (containing polypeptides L and NS) restored transcriptase activity at 31 degrees C in all combinations, but at 39 degrees C transcription was observed only in the presence of the supernatant fractions of wild-type and revertant viruses but not in the presence of the supernatant fractions of tsE1. When the pellet fractions and the L fractions were reconstituted, the transcriptase activity was restored in all combinations both at 31 degrees C and 39 degrees C. However, in vitro transcription at 39 degrees C by reconstituted pellet and L fractions was strongly inhibited when the NS fraction of tsE1 was also added, while addition of the NS fractions of wild-type and revertant viruses had no effect. Since only traces of polypeptide NS were present in the L fractions and none in the pellet fractions, the results strongly suggest that polypeptide L is the transcriptase itself while polypeptide NS exerts some control over transcription.
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PMID:The role of polypeptides L and NS in the transcription process of vesicular stomatitis virus New Jersey using the temperature-sensitive mutant tsE1. 298 93


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