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Query: UMLS:C0038362 (
stomatitis
)
8,852
document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)
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.
...
PMID:Effect of analogues of S-adenosylmethionine on in vitro polyadenylation by vesicular stomatitis virus. 256 41
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.
...
PMID:Homocysteine potentiates the antiviral and cytostatic activity of those nucleoside analogues that are targeted at S-adenosylhomocysteine hydrolase. 273 35
TsG16(I) is a temperature-sensitive (ts) mutant of vesicular
stomatitis
virus, Indiana serotype, which overproduces polyadenylic acid [poly(A)] in an in vitro transcription system due to a mutation in the L protein. Others have reported that L-
S-adenosylhomocysteine
(S-Ado-Hcy) causes wild-type (wt) virus to overproduce poly(A) in vitro. The possibility that tsG16(I) constitutively expresses a property induced by S-Ado-Hcy in the case of wt virus was found not to be so since polyadenylation by the mutant was still sensitive to S-Ado-Hcy. Indeed, S-Ado-Hcy caused tsG16(I) to overproduce poly(A) in vitro to a greater extent than its parental wt virus. The increase in polyadenylation observed in response to saturating levels of S-Ado-Hcy differed for tsG16(I), for its parental wt virus and for another wt strain. To characterize which viral protein modulated the polyadenylation response to S-Ado-Hcy, purified virions were fractionated and their phenotypes in homologous and heterologous reconstitution assays were examined. The results indicated that the viral L protein modulated the response in all three stocks of virus. These data provide further evidence to suggest that the L protein of vesicular
stomatitis
virus plays a role in polyadenylation of the viral mRNA.
...
PMID:The L protein of vesicular stomatitis virus modulates the response of the polyadenylic acid polymerase to S-adenosylhomocysteine. 284 66
For a series of adenosine analogues a close correlation (r = 0.986) was found between their antiviral potency (against vesicular
stomatitis
virus) and their inhibitory effects (Ki/Km) on
S-adenosylhomocysteine
(AdoHcy) hydrolase; thus, in order of increasing inhibitory potency for both virus replication and AdoHcy hydrolase activity: (S)-9-(2,3-dihydroxypropyl)adenine less than (RS)-3-adenin-9-yl-2-hydroxypropanoic acid (isobutyl ester) less than carbocyclic 3-deazaadenosine less than neplanocin A. Our findings point to AdoHcy hydrolase as the target for the broad-spectrum antiviral activity of these adenosine analogues.
...
PMID:Antiviral potency of adenosine analogues: correlation with inhibition of S-adenosylhomocysteine hydrolase. 298 50
A fraction of the viral mRNA synthesized in interferon-treated HeLa cells infected with vesicular
stomatitis
virus (VSV) lacks the 7-methyl group in the 5'-terminal guanosine of the cap; this mRNA is not associated with polyribosomes and does not bind to ribosomes in an assay for initiation of protein synthesis (de Ferra, F., and Baglioni, C. (1981) Virology 112, 426-435). To establish whether this defect in methylation is due to changes in the level of the methyl donor S-adenosylmethionine (AdoMet) and of its competitive inhibitor
S-adenosylhomocysteine
(AdoHcy), we measured the concentration of these compounds in HeLa cells treated with interferon. An increase in both AdoMet and AdoHcy was detected 3 to 6 h after addition of interferon. The level of these compounds increased gradually and in proportion to the interferon concentration used. With 125 reference units/ml of beta interferon, for example, the AdoHcy concentration increased more than 3-fold and that of AdoMet about 1.5-fold with a consequent change in the AdoHcy/AdoMet ratio. An increased AdoHcy/AdoMet ratio was also found in HeLa cells treated with pure alpha 2 interferon produced in Escherichia coli by recombinant DNA techniques. When the methylation of VSV mRNA was measured in assays carried out with permeabilized virions at the AdoHcy and AdoMet concentrations found in interferon-treated cells, a preferential inhibition of the viral (guanine-7-)methyltransferase activity was observed. Such an inhibition may account for the synthesis of VSV mRNA lacking the 7-methyl group of guanosine in the cap.
...
PMID:Increase in S-adenosylhomocysteine concentration in interferon-treated HeLa cells and inhibition of methylation of vesicular stomatitis virus mRNA. 618 92
Dansylcadaverine, amantadine, and rimantadine, which have been shown to inhibit the endocytosis of alpha 2-macroglobulin, epidermal growth factor, and vesicular
stomatitis
virus [Schlegel, R., Dickson, R. B., Willingham, M. C. & Pastan, I. (1982) Proc. Natl. Acad. Sci. USA 79, 2291-2295], were found to decrease phosphatidylcholine synthesis, chemotaxis, and internalization of a formylated peptide but to stimulate the incorporation of inositol into phosphatidylinositol in rabbit neutrophils. Dansylcadaverine decreased phosphatidylcholine synthesis by both the CDP-choline and transmethylation pathways and also inhibited the synthesis of phosphatidylethanolamine by the CDP-ethanolamine pathway. Dansylcadaverine had no effect on the phosphocholine, CDP-choline, or
S-adenosyl-L-homocysteine
pools but increased 2-fold the S-adenosyl-L-methionine pool. These results suggest that dansylcadaverine in some manner inhibited the condensation of CDP-choline with diacylglycerol to form phosphatidylcholine. Dansylcadaverine also inhibited phosphatidylcholine synthesis in human neutrophils, human fibroblasts, chicken embryo fibroblasts, rat hepatocytes, osteosarcoma cells, and neuroblastoma cells. It did not stimulate phosphatidylinositol synthesis in chicken embryo fibroblasts.
...
PMID:Inhibitors of endocytosis perturb phospholipid metabolism in rabbit neutrophils and other cells. 657 51
TsG16(I) is a temperature-sensitive mutant of vesicular
stomatitis
virus. In vitro, at the permissive temperature (31 degrees), it makes long poly(A) tracts, shows a larger increase in polyadenylation in the presence of
S-adenosyl-homocysteine
than its parental wt(Glasgow) virus, and makes an excess of polycistronic mRNA. In vitro transcription is also more thermosensitive than that of wt virus. Previous work suggested that there are at least two mutations in the L gene of tsG16(I), one effecting the poly(A)-associated phenotypes, the polycistronic phenotype, and the ability to grow at 34.7 degrees, the other affecting in vitro thermosensitivity for transcription and ability to grow at 37 degrees. We report further characterization of two revertants: 35G16p25, which grows at 34.7 degrees and has regained the wt poly(A),
SAH
and polycistronic RNA phenotypes; and 37G16p25, isolated from 35G16p25 based on growth at 37 degrees, which has regained the wt phenotype for in vitro thermosensitivity of transcription. Both revertants were shown to be due to intracistronic reversion[s] in the L gene. Sequencing of the L genes indicated that the tsG16(I) poly(A),
SAH
, polycistronic RNA, and growth at 34.7 degrees phenotypes were associated with amino acid 1488 phenylalanine-->serine and that transcription thermosensitivity and growth at 37 degrees were associated with changes in cysteine 1291.
...
PMID:Amino acid changes in the L polymerase protein of vesicular stomatitis virus which confer aberrant polyadenylation and temperature-sensitive phenotypes. 838 56
Treatment of the 6-aldehyde derived by Moffatt oxidation of 3-O-benzoyl-1,2-O-isopropylidene-alpha-D-ribo-hexofuranose (2c) with the dibromo- or bromofluoromethylene Wittig reagents generated in situ with tetrabromomethane or tribromofluoromethane, triphenylphosphine, and zinc gave the dihalomethyleneheptofuranose analogues 3b and 3d, respectively. Acetolysis, coupling with adenine, and deprotection gave 9-(7,7-dibromo-5,6, 7-trideoxy-beta-D-ribo-hept-6-enofuranosyl)adenine (5a) or its bromofluoro analogue 5b. Treatment of 5a with excess butyllithium provided the acetylenic derivative 9-(5,6, 7-trideoxy-beta-D-ribo-hept-6-ynofuranosyl)adenine (6). The doubly homologated vinyl halides 5a and 5b and acetylenic 6 adenine nucleosides were designed as putative substrates of the "hydrolytic activity" of
S-adenosyl-L-homocysteine
(AdoHcy) hydrolase. Incubation of AdoHcy hydrolase with 5a, 5b, and 6 resulted in time- and concentration-dependent inactivation of the enzyme (K(i): 8.5 +/- 0.5, 17 +/- 2, and 8.6 +/- 0.5 microM, respectively), as well as partial reduction of enzyme-bound NAD(+) to E-NADH. However, no products of the "hydrolytic activity" were observed indicating these compounds are type I mechanism-based inhibitors. The compounds displayed minimal antiviral and cytostatic activity, except for 6, against vaccinia virus and vesicular
stomatitis
virus (IC(50): 15 and 7 microM, respectively). These viruses typically fall within the activity spectrum of AdoHcy hydrolase inhibitors.
...
PMID:Doubly homologated dihalovinyl and acetylene analogues of adenosine: synthesis, interaction with S-adenosyl-L-homocysteine hydrolase, and antiviral and cytostatic effects. 1073 51
Ever since the
S-adenosylhomocysteine
(AdoHcy,
SAH
) hydrolase was recognized as a pharmacological target for antiviral agents (J. A. Montgomery et al., J. Med. Chem. 25:626-629, 1982), an increasing number of adenosine, acyclic adenosine, and carbocyclic adenosine analogues have been described as potent
SAH
hydrolase inhibitors endowed with broad-spectrum antiviral activity. The antiviral activity spectrum of the
SAH
hydrolase inhibitors include pox-, rhabdo-, filo-, arena-, paramyxo-, reo-, and retroviruses. Among the most potent
SAH
hydrolase inhibitors and antiviral agents rank carbocyclic 3-deazaadenosine (C-c3 Ado), neplanocin A, 3-deazaneplanocin A, the 5'-nor derivatives of carbocyclic adenosine (C-Ado, aristeromycin), and the 2-halo (i.e., 2-fluoro) and 6'-R-alkyl (i.e., 6'-R-methyl) derivatives of neplanocin A. These compounds are particularly active against poxviruses (i.e., vaccinia virus), and rhabdoviruses (i.e., vesicular
stomatitis
virus). The in vivo efficacy of C-c3 Ado and 3-deazaneplanocin A has been established in mouse models for vaccinia virus, vesicular
stomatitis
virus, and Ebola virus.
SAH
hydrolase inhibitors such as C-c3Ado and 3-deazaneplanocin A should in thefirst place be considered for therapeutic (or prophylactic) use against poxvirus infections, including smallpox, and hemorrhagic fever virus infections such as Ebola.
...
PMID:John Montgomery's legacy: carbocyclic adenosine analogues as SAH hydrolase inhibitors with broad-spectrum antiviral activity. 1643 25
Two alternate mechanisms of mRNA capping for spring viremia of carp virus have been observed. Under normal reaction conditions, a ppG residue of the capping GTP is transferred to a pA moiety of the 5' termini of mRNA transcripts. However, in reaction conditions where GppNHp is used instead of GTP, an alternate capping mechanism occurs whereby a pG residue of the capping GTP is transferred to a ppA moiety of the transcripts. The first mechanism is identical to that described previously for vesicular
stomatitis
virus (G. Abraham, D. P. Rhodes, and A. K. Banerjee, Nature [London] 255:37-40, 1975; A. K. Banerjee, S. A. Moyer, and D. P. Rhodes, Virology 61:547-558, 1974), and thus appears to be a conserved function during the evolution of rhabdoviruses. The alternate mechanism of capping indicates not only that capping can take place by two procedures, but also that the substrate termini have di- or triphosphate 5' ends, indicating that they are probably independently initiated. An analog of ATP, AppNHp, has been found to completely inhibit the initiation of transcription by spring viremia of carp virus, suggesting that a cleavage between the beta and gamma phosphates of ATP is essential for the initiation of transcription. However, in the presence of GppNHp, uncapped (ppAp and pppAp), capped (GpppAp), and capped methylated (m7GpppAmpAp and GpppAmpAp) transcripts are detected. Size analyses of oligodeoxythymidylic acid-cellulose-bound transcripts resolved by formamide gel electrophoresis demonstrated that full-size mRNA transcripts are synthesized as well as larger RNA species. The presence of GppNHp and
S-adenosylhomocysteine
in reaction mixtures did not have any effect on the type of unmethylated transcription products. Our results favor a transcription model postulated previously (D. H. L. Bishop, in H. Fraenkel-Conrat and R. R. Wagner, ed., Comprehensive Virology, vol. 10, Plenum Press, New York, 1977; D. H. L. Bishop and A. Flamand, in D. C. Burke and W. C. Russell, ed., Control Processes in Virus Multiplication, Cambridge University Press, Cambridge, 1975; D. H. L. Bishop and M. S. Smith, in D. Nayak, ed., The Molecular Biology of Animal Viruses, Marcel Dekker, New York, 1977; P. Roy and D. H. L. Bishop, J. Virol. 11:487-501, 1973) in which mRNA synthesis is initiated independently; they do not support a model for transcripts being synthesized by plus-strand cleavage (A. K. Banerjee, G. Abraham, and R. J. Colonno, J. Gen. Virol. 34:1-8, 1977; A. K. Banerjee, R. J. Colonno, D. Testa, and M. T. Franze-Fernandez, in B. M. J. Mahy and R. D. Barry, ed., Negative Strand Viruses and the Host Cells, Academic Press, London, 1978).
...
PMID:Alternate capping mechanisms for transcription of spring viremia of carp virus: evidence for independent mRNA initiation. 1678 87
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