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Query: UMLS:C0038362 (stomatitis)
 8,852 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Two conditional transcriptase-negative mutants of vesicular stomatitis virus (VSV) serotype New Jersey, tsB1 and tsF1, their revertants tsB1/R1 and tsF1/R1 and the wildtype virus were dissociated into pellet, NS and L fractions and, after reconstitution of these in various combinations, the transcriptase activities were assayed in vitro at the permissive (31 degrees C) and restrictive (39 degrees C) temperatures. The pellet fractions contained the virion RNA-polypeptide N complexes, while the NS and L fractions were essentially pure preparations of these polypeptides. The synthesis of RNA by the reconstituted pellet and L fractions was inhibited at 39 degrees C only when the L fractions of tsB1 or tsF1 were used. Addition of the NS fractions to the reconstituted pellet and L fractions did not alter the rates of RNA synthesis. These results demonstrate that polypeptide L is the temperature-sensitive polypeptide of both mutants tsB1 and tsF1 and support previous observations that polypeptide L is the transcriptase itself. The fact that a second mutant of complementation group F, tsF2, is transcriptase-positive but replicase-negative suggests that polypeptide L is involved both in transcription and replication. Intracistronic complementations may account for the observation that the temperature-sensitive mutations affect polypeptide L in complementation groups B and F.
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PMID:Temperature sensitivity of the transcriptase of mutants tsB1 and tsF1 of vesicular stomatitis virus New Jersey is a consequence of mutation affecting polypeptide L. 299 27

The large gene, L, of vesicular stomatitis virus (VSV), which codes for the multifunctional RNA-dependent RNA polymerase, was assembled from five overlapping cDNA clones. The sequence of the 6.4-kilobase gene of the final construct was identical to the consensus sequence reported earlier. The gene was inserted into the simian virus 40 transient expression vector pJC119. Antibodies directed against synthetic peptides corresponding to the amino and carboxyl termini of the L protein were raised in rabbits. Both antibodies specifically immunostained the cytoplasm of COS cells that had been transfected with the vector DNA. The expressed L protein was immunoprecipitated from cell extracts and it was identical in size to the L protein of the virion (241 kilodaltons). Most importantly, COS cells that expressed the recombinant L protein transcribed, replicated, and consequently complemented and rescued temperature-sensitive RNA polymerase mutants of VSV at the nonpermissive temperature. The kinetics of virus release were similar to those of a wild-type VSV infection. We conclude that the recombinant RNA polymerase protein L is indistinguishable in its size and its functions from the VSV polymerase.
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PMID:Expression of a cDNA encoding a functional 241-kilodalton vesicular stomatitis virus RNA polymerase. 299 88

Indomethacin blocks the biosynthesis of vesicular stomatitis virus (VSV) at the level of primary transcription, RNA replication, and protein synthesis (P. K. Mukherjee and R. W. Simpson (1985), Virology 140, 188-191). Nucleocapsids of infecting virus particles recovered from indomethacin-treated cells were analyzed for in vitro transcriptase activity. Incorporation of [3H]UTP in mixtures containing nucleocapsids from HEp-2 cells pretreated with 10(-3) M indomethacin was inhibited approximately 80% compared to control reactions containing nucleocapsids from untreated infected cells. The level of inhibition of in vitro transcriptase activity of viral nucleocapsids from drug-treated cultures varied according to the cell line used for infection. After indomethacin removal, cells regained their ability to produce enzymatically competent viral-transcribing complexes unless they were subsequently exposed to metabolic inhibitors such as actinomycin D or alpha-amanitin. Enzymatically defective nucleocapsids from indomethacin-treated cells showed enhanced in vitro transcriptase activity in the presence of modulators of prostaglandins and cyclic nucleotides. Electrophoretic analysis of product from in vitro transcriptase reactions revealed that these defective nucleocapsids are unable to synthesize VSV messenger RNA or normal size leader RNA species but only smaller transcripts of undetermined identity.
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PMID:Transcriptionally defective nucleocapsids of vesicular stomatitis virus from cells treated with indomethacin. 302 67

We have now completed the rabies genome structure by the cloning and the sequencing of the entire L gene and the 5' untranscribed region. The L gene encodes a single open reading frame 2142 amino acids in length (244,206 Da) that corresponds to the viral RNA-dependent RNA polymerase. In contrast with other isofunctional proteins, the rabies polymerase exhibits a high degree of homology with the vesicular stomatitis virus polymerase, and a lesser degree, although significant, with those of Sendai virus and Newcastle disease virus, which suggests a differential evolution of the different cistrons. We have observed several strongly conserved stretches which may designate the independent functional domains of this multifunctional protein. In addition to the conservation of related transcription signals (N. Tordo et al. (1986) Proc. Natl. Acad. Sci. USA 83, 3914-3918.), this highlights the striking selective pressure on elements involved in transcription and replication mechanisms, and provides further evidence for a common ancestry of Rhabdoviridae and Paramyxoviridae families. The terminal complementarity observed in the rabies genome suggests the conservation of important genomic signals.
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PMID:Completion of the rabies virus genome sequence determination: highly conserved domains among the L (polymerase) proteins of unsegmented negative-strand RNA viruses. 340 52

A procedure has been developed for the sequential removal and purification of the glycoprotein and membrane protein of vesicular stomatitis virus (VSV). Neither of these proteins exhibited transcriptase activity. All of the activity was recovered in the ribonucleic acid (RNA)-ribonucleoprotein complex of VSV, which also has four other minor proteins associated with it. During transcription of 41% of the RNA of a virus preparation, no dissociation of the ribonucleoprotein from the viral RNA was observed.
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PMID:Dissociation of vesicular stomatitis virus and relation of the virion proteins to the viral transcriptase. 434 41

Transcriptase activity was dissociated from vesicular stomatitis virions by highionic-strength buffer containing Triton X-100. Considerable enzyme activity could be restored by recombining inactive sedimentable and nonsedimentable virion fractions. Reconstituted transcriptase activity was dependent on the presence of all four nucleoside triphosphates and the concentration of heat-labile molecules in both supernatant and pellet fractions. Lower NaCl concentrations removed approximately 46% of virion protein, but did not release transcriptase activity from the pellet fraction, nor could incorporation of (3)H-uridine-5'-triphosphate by complete virions be increased by adding soluble transcriptase. Evidence that the virion nucleocapsid is the transcription template was provided by finding that the pellet contained predominantly virion core nucleoprotein, ribonucleic acid, and homogeneous nucleocapsid coils when viewed by electron microscopy. Removal of envelope G and M proteins by Triton and low-salt buffer without decreasing nucleocapsid polymerase activity indicates that neither G nor M protein is necessary for transcription. Additional data are required to determine whether the minor nucleocapsid proteins L or NSl, or both, which are at least partially solubilized in high-salt buffer, are the transcriptase. Preliminary data suggest that the major N nucleoprotein, which was not solubilized by high-salt buffer, is also required for transcription. Defective T virions contained at least as much transcriptase per weight as did B virions, as determined by restoration with T supernatant fluids of transcription function to B nucleocapsid template. However, the T nucleocapsid would not serve as template for B or T transcriptase, a finding which is interpreted as evidence of T template defectiveness. The presence of defective T nucleocapsids did not interfere with B or T transcriptase function reconstituted with B template.
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PMID:Dissociation and reconstitution of the transcriptase and template activities of vesicular stomatitis B and T virions. 434 47

The viral ribonucleic acids (RNA species) synthesized in HeLa cells infected with temperature-sensitive (ts) mutants and with the wild type of vesicular stomatitis virus at permissive (30 C) and nonpermissive (39.2 C) temperatures were compared by sucrose gradient centrifugation. Two ts mutants (ts 5 and ts 100) representing two separate complementation groups (respectively, groups I and IV), each concerned with viral RNA synthesis, were chosen. Mutant ts 5 failed to synthesize any RNA at 39.2 C. Under the same conditions, mutant ts 100 showed a low, but easily detectable, synthesis of RNA without characteristic peaks. The in vitro transcriptase activity was tested with mutants ts 5 and ts 100 at 39.2 C: normal activity, compared with wild-type virus, was detected with purified ts 100, but no activity was detected with purified ts 5. From all our data we conclude that mutant ts 5 is defective in transcription. The defect could be in the structural transcriptase enzyme or at the level of template for transcription. Results with mutant ts 100 were not so clear-cut. However, we suggest that this mutant is concerned with some aspect of transcription in vivo. In addition, our results lead us to postulate some linkage between transcription and replication.
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PMID:Study of the transcription and the replication of vesicular stomatitis virus by using temperature-sensitive mutants. 434 55

The initiation of RNA transcription by the virion-bound RNA transcriptase of vesicular stomatitis virus has been examined. Multiple initiation sequences have been observed, two of which have been characterized (pppApCpGp... and pppGpCp...) suggestive of a transcription process which can start at different sites along the template RNA. By the use of sequential labeling techniques and exonucleases, it has been determined that there is a 5' to 3' direction of product RNA synthesis.
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PMID:Initiation and direction of RNA transcription by vesicular stomatitis virus virion transcriptase. 434 90

T-particle-free stocks of temperature-sensitive mutants representing the four Glasgow complementation groups of the Indiana serotype of vesicular stomatitis virus were used to study RNA synthesis at the permissive and nonpermissive temperatures of 31 and 39 C, respectively. Mutants selected from the four Glasgow complementation groups were characterized on the basis of particle and ribonucleoprotein formation. Intracellular RNAs were further characterized by polyacrylamide gel electrophoresis. ts G22 (group II) and ts G41 (group IV), previously characterized as RNA negative at the nonpermissive temperature, synthesized low levels of RNA which could not be attributed to contaminating levels of revertants. Furthermore, the levels of synthesis could not be reduced by the addition of cycloheximide. These data suggest that ts G22 (group II) and ts G41 (group IV) contain a thermally stable, virion-encapsidated transcriptase, but fail to amplify RNA synthesis due to a thermally labile function presumably necessary for the synthesis of viral RNA. ts G31, a group III mutant, synthesized intracellular RNA at amplified levels at the nonpermissive temperature. Intracellular ribonucleoprotein complexes were isolated in copious amounts; however, no particles corresponding in size to finished virions were observed. These data suggest a thermally labile maturation factor or envelope associated structural protein to be defective in ts G31 (group III). ts G11 (group 1) showed no detectable RNA synthesis at the nonpermissive temperature. These data suggest ts G11 (group I) contains a thermally labile component involved in early transcription. This group may contain a number of mutants defective in different components of the transcription apparatus, which may not complement in vivo because of the physical improbability of subunit exchange between virion particles of the incoming inoculum.
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PMID:RNA synthesis in temperature-sensitive mutants of vesicular stomatitis virus. 435 55

The synthesis of viral RNA by wild-type vesicular stomatitis virus (L(1)VSV) and a small, plaque-size mutant (S(2)VSV) was studied in vitro and in chicken embryo (CE) and mouse L-cell cultures. Virus-specific RNA synthesized in CE or L cells infected with either L(1) or S(2)VSV at low multiplicity was of the same size classes, 12 to 15S, 28S, and 38S. The major differences were in the proportion of RNA produced of each size class. L(1)VSV always synthesized larger proportions of 38S RNA, and S(2)VSV produced larger proportions of 12 to 15S RNA. Both S(2) and L(1)VSV exhibited RNA transcriptase activity in vitro and in cell culture. The products of the in vitro reaction were the same, 12 to 15S for both. The products of the virion-associated transcriptase in CE or L-cell cultures in the presence of cycloheximide were also the same for both viruses but differed from the in vitro products in that 28S and 12 to 15S RNA were made. The effects of addition of cycloheximide at various times after infection demonstrated that new protein synthesis is required early (0-2 h) for both S(2) and L(1)VSV to initiate and maintain the normal rate of viral RNA synthesis. However, the overall rate of RNA synthesis in L(1)VSV infections became independent of protein synthesis after 2 h whereas the rate in S(2)VSV infections did not. With either virus, synthesis of 38S RNA did not occur in the absence of protein synthesis. Moreover, continuous 38S RNA production required continuous protein synthesis. Production of 38S RNA ceased within 30 min after addition of cycloheximide to S(2) (-) or L(1)VSV-infected CE or L cells that had already begun to synthesize the 38S form. The cycloheximide-induced cessation of 38S RNA synthesis was accompanied by a marked increase in production of 12 to 15S and 28S RNA in L(1)VSV-infected cells, but no increase in synthesis of small RNA species occurred in S(2)VSV-infected cells.
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PMID:RNA synthesis by vesicular stomatitis virus and a small plaque mutant: effects of cycloheximide. 435 30


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