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 phosphorylated state of the vesicular stomatitis virus phosphoprotein (P), an essential component of the virion-associated RNA polymerase complex, has been shown to be important for the transcriptional activity of the complex. Recent studies indicate that phosphorylation within the acidic domain of the P protein by cellular casein kinase II is necessary for its activity. In an attempt to identify the exact location of the cell kinase-mediated phosphorylation, we altered specific serine and threonine residues within the acidic domain of the New Jersey serotype of P protein by site-directed mutagenesis. The altered P proteins were then tested to determine what effect these mutations had on the phosphorylated state of the protein in vivo as well as its transcriptional activity in vitro. We report that serine residues 59 and 61 within the acidic domain of the P protein must be phosphorylated for it to be functionally active in a reconstituted transcription assay. These results demonstrate the importance of site-specific phosphorylation in the transcriptional activity of a negative-strand RNA viral phosphoprotein and the crucial role played by a cell protein kinase in this process.
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PMID:Phosphorylation of specific serine residues within the acidic domain of the phosphoprotein of vesicular stomatitis virus regulates transcription in vitro. 132 45

The phosphoprotein NS of vesicular stomatitis virus which accumulates within the infected cell cytoplasm is phosphorylated at multiple serine and threonine residues (G. M. Clinton and A. S. Huang, Virology 108:510-514, 1981; Hsu et al., J. Virol. 43:104-112, 1982). Using incomplete chemical cleavage at tryptophan residues, we mapped the major phosphorylation sites to the amino-terminal half of the protein. Analysis of phosphate-labeled tryptic peptides suggests that essentially all of the label is within the large trypsin-resistant fragment predicted from the sequence of Gallione et al. (J. Virol. 39:52-529, 1981). A similar result has been obtained for NS protein isolated from the virus particle by C.-H. Hsu and D. W. Kingsbury (J. Biol. Chem., in press). Analysis of phosphodipeptides utilizing the procedures of C. E. Jones and M. O. J. Olson (Int. J. Pept. Protein Res. 16:135-142, 1980) enabled us to detect as many as six distinct phosphate-containing dipeptides. From these studies, together with the known sequence data, we conclude that the major phosphate residues on cytoplasmic NS protein are located in the amino third of the NS molecule and most probably between residues 35 and 106, inclusive. The studies also provide formal chemical proof that NS protein has a structure consistent with a monomer of the sequence of Gallione et al. as modified by J. K. Rose (personal communication). The low electrophoretic mobility of this protein on sodium dodecyl sulfate-polyacrylamide gel electrophoresis is not therefore due to dimerization.
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PMID:Phosphorylation sites on phosphoprotein NS of vesicular stomatitis virus. 298 24

The complete nucleotide sequence of the NS mRNA of vesicular stomatitis virus (New Jersey serotype) was established from two cDNA clones spanning the entire coding region of the mRNA. The gene is 856 nucleotides long and can code for a polypeptide of 274 amino acids. Comparison with the nucleotide sequence of the NS gene of the Indiana serotype revealed only 41% sequence homology. The deduced amino acid sequences of the NS proteins were only 32% homologous, with no identical stretches of more than five amino acids. However, at the C-terminal domain there was a conserved region of 21 amino acids with greater than 90% homology. Surprisingly, relative hydropathicity plots also demonstrated the presence of a large number of hydrophilic amino acids sequestered similarly over the N-terminal half of the protein. In addition, the total number of serine and threonine residues, presumptive phosphorylation sites, was similar and included seven serine and three threonine residues located at identical positions. It appears that during divergent evolution of these two vesicular stomatitis virus serotypes from a common ancestor, considerable mutation occurred in the main body of the gene but the overall structure of the protein was retained. The function of the NS protein in relation to the evolution of the two viruses is discussed.
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PMID:Vesicular stomatitis virus NS proteins: structural similarity without extensive sequence homology. 298 60

The phosphoprotein (NS) gene from the Indiana serotype of vesicular stomatitis virus (VSV; Mudd-Summers strain) was cloned and sequenced. The NS gene encodes a protein of 265 amino acids which was expressed from a simian virus 40 vector in COS cells. The post-translational modification characteristic of viral NS, the extensive phosphorylation of a cluster of serine and threonine residues, was also evident in recombinant NS protein. The NS gene displays a property common to the phosphoprotein genes of negative-strand RNA viruses: the phosphoprotein mRNA has a second open reading frame (ORF) which could encode a small (7500 mol. wt.) protein. Both measles virus and Sendai virus employ the second ORF of their phosphoprotein gene, and the resultant proteins have an amino acid composition similar to that predicted for the VSV ORF. Comparison of phosphoproteins from different VSV strains revealed two conserved domains that we propose are critical for the function of NS in transcription and replication.
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PMID:Cloning and expression of a viral phosphoprotein: structure suggests vesicular stomatitis virus NS may function by mimicking an RNA template. 301 52

The nucleotide sequence of the 3' end of the genome of Chandipura (CHP) virus, including the complete sequences of the nucleocapsid (N) and phosphoprotein (NS) genes was determined, principally from cloned cDNAs of the N and NS mRNAs. The NS mRNA of CHP virus is 908 bases in length and encodes a protein of 293 amino acids. Comparison of the CHP virus NS protein sequence with those of vesicular stomatitis virus of the New Jersey serotype (VSV (NJ)) and of the Indiana serotype (VSV (IND] revealed homologies of only 23 and 21%, respectively, with no consecutive stretches of more than four amino acids identical among the three sequences. As with the two VSV serotypes, the highest homology between the NS proteins of CHP and VSV was in a 20-amino acid region near the carboxy termini of the proteins. Of the potential phosphorylation sites, there are eight conserved serine or threonine residues among the three sequences. Despite the dissimilarity among primary sequences of the NS proteins, their overall structure, as assessed by amino acid composition and by the relative hydropathicities of the sequences, has been conserved throughout evolution. The N mRNA of CHP virus is 1291 bases long and encodes a protein of 422 amino acids. In contrast to the NS protein, the CHP N protein is at least 50% homologous to the N proteins of each of the VSV serotypes. We have identified a region near the center of these N protein sequences which is conserved among members of both the rhabdovirus and paramyxovirus families. This extent of conservation of the N protein sequences underscores the high rate of mutability of the NS protein sequences among the vesiculoviruses.
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PMID:Sequences of Chandipura virus N and NS genes: evidence for high mutability of the NS gene within vesiculoviruses. 302 73

Semliki forest virus and Sindbis virus (Alphaviruses belonging to the togavirus group) grown in BHK-21 cells possessed very low levels of virion-associated protein kinase activity. For comparison, vesicular stomatitis virus, also grown in BHK-21 cells, contained a virion-bound protein kinase which had a specific activity 80 times greater than that of the Alphaviruses. The Alphavirus protein kinase was unmasked by the nonionic detergent Nonidet P-40 but was not activated by cyclic nucleotides. Phosvitin was the best exogenous phosphate acceptor for assaying the viral enzyme in vitro. Phosphoprotein phosphatase activity was also detected in the Alphaviruses. Both in vivo and in vitro, all of the viral structural polypeptides were phosphorylated, and the phosphorylated amino acids were found to be serine and threonine. The viral nucleocapsid protein was about four times more efficient as a phosphate acceptor than were the envelope proteins. From 33 to 50% of the total protein kinase was bound to the viral nucleocapsid, and the specific activity of this enzyme was 4 to 10 times greater than that associated with the viral envelope.
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PMID:Virion-bound protein kinase in Semliki forest and Sindbis viruses. 436 99

Among the protein kinases associated with vesicular stomatitis virus (VSV), one was identified by immunoprecipitation to be pp60src, the transformation-specific product coded for by avian sarcoma virus, or its endogenous cellular homolog. This activity phosphorylated only tyrosine. pp60src was enriched in the membranes, whereas the serine- and threonine-specific kinases were concentrated with viral cores. The content of pp60src in VSV can be manipulated by growing VSV in different host cells. Monolayer baby hamster kidney cells transformed by an avian sarcoma virus produced VSV progeny which contained 7-fold greater pp60src activity than progeny produced by control untransformed or revertant cells. In contrast, suspension cultures of baby hamster kidney cells which produced VSV with increased tyrosine-specific kinase activity did not affect the content of pp60src. When pp60src was specifically increased in cells, the endogenous phosphorylation of tyrosine residues in the VSV matrix M protein was also enhanced, to as much as 20-fold. The phosphorylation of serine or threonine in this protein or in the other VSV phosphoprotein NS was not affected. Cellular tyrosine-specific kinases other than pp60scr did not change the overall phosphorylation pattern of any VSV phosphoproteins. Experiments designed to test the effects of endogenous phosphorylation on the various functions of the M protein failed to detect any significant alterations.
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PMID:Host-dependent phosphorylation and kinase activity associated with vesicular stomatitis virus. 627 33

Our long-term goal is to define the catalytic domains of the L protein subunit of the Sendai virus RNA polymerase. An aberrant polyadenylation phenotype in the vesicular stomatitis virus tsG16 L protein mutant has recently been identified as a phenylalanine to serine change at amino acid 1488 (Hunt and Hutchinson, Virology 193, 786-793, 1993). To test if functional domains are conserved in the L proteins of negative-strand RNA viruses, we attempted to create a similar polyadenylation defect in the Sendai virus L protein. Nine different amino acid substitutions at the analogous site in the Sendai L protein (cysteine at amino acid 1571) were constructed by site-directed mutagenesis of the gene. Each mutant L protein was synthesized and bound to the Sendai P protein to form the P-L polymerase complex. While none of these L mutants exhibited a change in polyadenylation, the single amino acid changes yielded a variety of activities in vitro. Mutants containing valine, leucine, or phenylalanine at amino acid 1571, amino acids found naturally in the L proteins of other paramyxoviruses, yielded polymerases that had biological activity equal to or better than the wild-type (WT) polymerase. Serine or threonine substitutions in the L protein at this position also resulted in polymerases with nearly WT synthetic activity. In contrast, a glycine substitution significantly decreased overall polymerase activity, whereas a tyrosine substitution gave decreased transcription, but virtually no DI genome replication in vitro. The tyrosine-substituted polymerase may be unable to carry out the packaging step of replication, since DI leader RNA synthesis was normal in this mutant. Mutant L proteins with basic arginine or histidine substitutions were inactive in all viral RNA synthesis in vitro, although the polymerase complexes could bind the nucleocapsid template.
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PMID:Alternative amino acids at a single site in the Sendai virus L protein produce multiple defects in RNA synthesis in vitro. 764 61

TsW16B is a temperature-sensitive mutant of vesicular stomatitis virus. Others have shown that it is temperature-sensitive for replication in vivo and for transcription in vitro and that these phenotypes are probably due to mutation of the N (nucleocapsid) gene. Five independent revertants were isolated from tsW16B based on their ability to grow at 39 degrees C. The thermosensitivity of in vitro transcription by these revertants was similar to that of the wild-type virus [wt(HR)] from which tsW16B was derived. Fractionation-reconstitution studies of two revertants indicated that the reversion was in the N or P (phosphoprotein) gene. The N and P genes of wt(HR), tsW16B, and these two revertants were sequenced. There were no differences between the P genes. Comparison of the predicted N protein sequences of wt(HR), tsW16B and the two revertants indicated that the growth and in vitro transcription phenotypes of tsW16B were due to a change of amino acid residue 238 from threonine to isoleucine. The amino acid at position 238 in the other three revertants also showed an exact reversion to threonine. Amino acid residue 238 lies in a domain of the N protein which is highly conserved among vesiculoviruses.
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PMID:Identification of an amino acid change that affects N protein function in vesicular stomatitis virus. 799 52

Certain large DNA viruses (e.g. herpesviruses and poxviruses) encode proteins related to cellular protein-serine/threonine kinases, and Hepatitis B virus and vesicular stomatitis virus may encode structurally different protein kinases. Other viruses activate cellular protein kinases, e.g. interferon-induced eukaryotic initiation factor-2 kinase, growth factor-induced kinases and protein kinases that regulate mitosis. Protein phosphatases are encoded by vaccinia virus and bacteriophage lambda and must also play a role in viral infection--as do cellular protein phosphatases. The functions of many of these viral enzymes remain to be determined, but they represent possible new targets for anti-viral therapy.
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PMID:Viral protein kinases and protein phosphatases. 830 96


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