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Query: UMLS:C0038362 (
stomatitis
)
8,852
document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)
Genomic replication of the negative-strand RNA viruses is dependent upon protein synthesis. To examine the requirement for protein synthesis in replication, we developed an in vitro system that supports the genome replication of defective interfering particles of the negative-strand rhabdovirus vesicular
stomatitis
virus (VSV), as a function of protein synthesis (Wertz, J. Virol. 46:513-522, 1983). The system consists of defective interfering nucleocapsid templates and an mRNA-dependent reticulocyte lysate to support protein synthesis. We report here an analysis of the requirement for individual viral proteins in VSV replication. Viral mRNAs purified by hybridization to cDNA clones were used to direct the synthesis of individual proteins in the in vitro system. By this method, it was demonstrated that the synthesis of the VSV nucleocapsid protein, N, alone, resulted in the replication of genome-length RNA by both defective interfering intracellular nucleocapsids and virion-derived nucleocapsids. Neither the viral
phosphoprotein
, NS, nor the matrix protein, M, supported RNA replication. The amount of RNA replication for a given amount of N protein was the same in reactions in which either all of the VSV proteins or only N protein were synthesized. In addition, RNA replication products synthesized in reactions containing only newly made N protein assembled with the N protein to form nucleocapsids. These results demonstrate that the major nucleocapsid protein (N) can by itself fulfill the requirement for protein synthesis in RNA replication and allow complete replication, i.e., initiation and elongation, as well as encapsidation of genome-length progeny RNA.
...
PMID:N protein alone satisfies the requirement for protein synthesis during RNA replication of vesicular stomatitis virus. 631 30
HIV-1 Vpu is a small transmembrane
phosphoprotein
of 16 kDa which performs critical roles in CD4 proteolysis and virus release. Previous studies have demonstrated that Vpu-induced degradation of CD4 occurs in the endoplasmic reticulum (ER), and that the proteolytic process is sequence specific requiring both the transmembrane and cytoplasmic domains of CD4. In the present study, we investigated the effects of Vpu expression on the intracellular membrane trafficking pathway of mammalian cells. In singly transfected cells, the HIV envelope glycoproteins and vesicular
stomatitis
virus glycoprotein (VSV G) were properly transported to the cell surface undergoing oligosaccharide modifications characteristic of their movement through the Golgi complex. In contrast, the cell surface delivery of glycoproteins was severely impeded in cells expressing Vpu. Biochemical analyses revealed that Vpu expression blocked the transfer of proteins from the ER-Golgi complex to the plasma membrane in a dose- and protein-dependent manner. Soluble gp120 exhibited extreme transport defects in the presence of Vpu, whereas transmembrane proteins (e.g., gp160, VSV) responded only moderately to wild-type Vpu. To gain insight into Vpu-mediated transport inhibition, we performed mutational analysis of the CK-2 phosphorylation sites (serines at 52 and 56) in the Vpu protein. CK-2 phosphorylation of Vpu has been shown to regulate the activity of the protein in reactions that involve the proteolysis of CD4 in the ER. We demonstrate here that the phosphorylation mutant is defective in both sequence-specific degradation of VRE-containing substrates and the transport inhibition of gp120 and VSV-G in the secretory pathway. Thus, these experiments have revealed that Vpu-mediated proteolysis and transport inhibition are mechanistically coupled requiring the same structural elements of the Vpu protein in both processes. We propose that the primary effect of Vpu expression is to impede the secretion process and then access glycoproteins bearing the VRE for Vpu-mediated proteolysis in the ER of mammalian cells.
...
PMID:The human immunodeficiency virus type 1 Vpu protein: a potential regulator of proteolysis and protein transport in the mammalian secretory pathway. 749 87
It was previously shown that the
phosphoprotein
(P) of vesicular
stomatitis
virus must undergo phosphorylation-dependent multimerization to become transcriptionally active. Phosphorylation at S-60 and/or T-62 by casein kinase II or substitution of these residues by D is required for multimer formation. We now find that substitution of either one of these residues by A prevents phosphorylation by casein kinase II and multimer formation. The binding of multimeric P to the other two transcriptional components of vesicular
stomatitis
virus (L protein and the N-RNA template) has been characterized by using P immobilized on beads through its poly(His) tag to facilitate recovery of bound complexes. Multimerization of P was absolutely required for binding to both L and template. Multimeric P combined with the polymerase enzyme (L) in a stoichiometric 1:1 complex, which bound to the N-RNA template much more strongly than multimeric P alone. Substitution of S-227 and S-233 by A residues had no effect on multimerization or binding of L to P but prevented binding of both P and L to template and abolished transcriptional activity. In contrast, substitution of these residues with D residues had no effect on template binding or activity. However, substitution at these sites by either D or A largely abolished phosphorylation by L-associated kinases, thus identifying S-227 and S-233 as the major sites targeted by these kinases and confirming that phosphorylation of P protein by L-associated kinases is without transcriptional effect.
...
PMID:Cooperative binding of multimeric phosphoprotein (P) of vesicular stomatitis virus to polymerase (L) and template: pathways of assembly. 749 81
Infectious vesicular
stomatitis
virus (VSV), the prototypic nonsegmented negative-strand RNA virus, was recovered from a full-length cDNA clone of the viral genome. Bacteriophage T7 RNA polymerase expressed from a recombinant vaccinia virus was used to drive the synthesis of a genome-length positive-sense transcript of VSV from a cDNA clone in baby hamster kidney cells that were simultaneously expressing the VSV nucleocapsid protein,
phosphoprotein
, and polymerase from separate plasmids. Up to 10(5) infectious virus particles were obtained from transfection of 10(6) cells, as determined by plaque assays. This virus was amplified on passage, neutralized by VSV-specific antiserum, and shown to possess specific nucleotide sequence markers characteristic of the cDNA. This achievement renders the biology of VSV fully accessible to genetic manipulation of the viral genome. In contrast to the success with positive-sense RNA, attempts to recover infectious virus from negative-sense T7 transcripts were uniformly unsuccessful, because T7 RNA polymerase terminated transcription at or near the VSV intergenic junctions.
...
PMID:Efficient recovery of infectious vesicular stomatitis virus entirely from cDNA clones. 766
We have developed a system in which vesicular
stomatitis
virus (VSV) minigenomes encoding viral structural proteins can be expressed from plasmids. These RNAs can be replicated, transcribed, and packaged into infectious particles when coexpressed with the other VSV proteins. The minigenomes contain either the glycoprotein (G protein) gene (GMG [stands for G minigenome]) or both the G and matrix (M) protein genes (GMMG [stands for G/M minigenome]) from the Indiana serotype of VSV flanked by the trailer and leader regions from the wild-type VSV genome. Northern (RNA) blot analysis showed that the minigenome RNAs were replicated and that a positive-sense replicative intermediate was synthesized when coexpressed with the nucleocapsid (N) protein and the two VSV polymerase proteins (
phosphoprotein
[P] and the large catalytic subunit [L]) in vivo. In addition, functional mRNAs were transcribed from the minigenome templates, and the appropriate encoded proteins were expressed. Expression of the G and M proteins from GMMG resulted in the assembly and release of infectious particles that could be passaged on cells expressing the N, P, and L proteins only. Amplification occurred during successive passages, and after four passages approximately 30% of the cells expressed both the G and M proteins. Analysis of the RNAs produced in the GMMG-infected cells also showed that the minigenomes accurately reproduced all of the replicative and transcriptional events that normally occur in a VSV-infected cell. GMMG is therefore a novel type of defective particle which encodes functional viral proteins critical to its own propagation.
...
PMID:Replication and amplification of novel vesicular stomatitis virus minigenomes encoding viral structural proteins. 770 20
Specific in vivo interaction between the
phosphoprotein
(P) and the large polymerase protein (L) from the Indiana serotype of vesicular
stomatitis
virus was studied using a two-hybrid system. Transfection of CHO cells with plasmids encoding GALPIND and VPLIND fusion proteins resulted in an easily detectable level of CAT activity, indicating that PIND and LIND associate in vivo in the absence of other viral proteins. Mutational studies of PIND demonstrated that both domains I and II of PIND are important for PIND-LIND association. In addition, casein kinase II (CKII)-mediated phosphorylation within domain I of PIND was necessary for efficient association with LIND. We have also used the two-hybrid system to show PIND interaction with NIND in vivo. PIND and NIND associated more strongly than PIND and LIND. A similar strong association was observed in heterologous interaction studies between Indiana and New Jersey serotype P and N proteins. Mutational studies of PIND demonstrated that, unlike what was found for PNJ-NNJ association, only the C-terminal region of the P protein was important for efficient association with NIND. Like PNJ, CKII-mediated phosphorylation within domain I of PIND was not required for P-N association and, like NNJ, the C-terminal five amino acids of the NIND protein were critical for P association with N. These results demonstrate the importance of phosphorylation and specific domains of the P protein in its interaction with the L and N proteins, which are necessary for viral transcription and replication, respectively.
...
PMID:Efficient interaction of the vesicular stomatitis virus P protein with the L protein or the N protein in cells expressing the recombinant proteins. 774 58
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.
...
PMID:Identification of an amino acid change that affects N protein function in vesicular stomatitis virus. 799 52
We have mapped the genome of lettuce necrotic yellows virus (LNYV), the type member of the genus cytorhabdovirus of the family Rhabdoviridae. We have cloned and sequenced all intergenic regions and the 3' leader and 5' trailer of the negative-sense, single-stranded RNA genome of LNYV. The LNYV genome appears to contain six genes, the five expected genes coding for the virion proteins, and a sixth gene of unknown function, as for sonchus yellow net virus (SYNV), a member of the genus nucleorhabdovirus. The proposed LNYV genomic map is 3'-N-4a-4b-M-G-L-5', where N is the nucleocapsid protein gene; 4a and 4b are two genes, one of which codes for the proposed
phosphoprotein
P and the other for a putative protein of unknown function; M is the proposed matrix protein gene; G is the proposed glycoprotein gene; and L is the proposed transcriptase gene. The different LNYV intergenic regions have highly conserved consensus sequences, which could be divided into three components: the sequences corresponding to the 3' end of the mRNAs, intergenic sequences of variable length, and the sequences corresponding to the 5' end of the mRNAs. A leader sequence of 84 nucleotides (nt) at the 3' end of the LNYV genomic RNA preceeded the N gene. A trailer sequence of 187 nt at the 5' end of the genomic RNA followed the L gene. A comparison between LNYV leader and trailer sequences revealed complementary 3' and 5' ends, which could give rise to a putative "panhandle" structure with a two bases overhang in the leader sequence. We have compared these sequences to the corresponding sequences of SYNV as well as to vesicular
stomatitis
virus (VSV) and rabies virus (RV), the type members of the vesiculovirus and lyssavirus genera, respectively, of animal rhabdoviruses. Homologies were found in the intergenic regions between LNYV, SYNV, VSV, and RV, at the 3' ends of the mRNAs. LNYV intergenic sequences were of variable lengths, as were those found in RV. The consensus sequences found at the 5' ends of LNYV mRNAs differed from the highly conserved consensus transcription start sequence UUGU/A found in SYNV, VSV, and RV. Conserved sequences were also found in the first 30 nt of the leader and the last 30 nt of the trailer, between LNYV, SYNV, VSV, and RV.
...
PMID:Genomic organization of lettuce necrotic yellows rhabdovirus. 817 30
The homologous and heterologous interactions between the nucleocapsid protein N and the
phosphoprotein
P of New Jersey and Indiana serotypes of vesicular
stomatitis
virus were studied. SP6 derived N and P mRNAs were cotranslated in rabbit reticulocyte lysate and the complexes formed thereof were analyzed by 7.5% nondenaturing polyacrylamide gel electrophoresis. P protein of VSV(NJ) has two binding sites for homologous N protein: One located within the C-terminal 11 amino acids (within domain III) is responsible for the formation of five specific complexes while the other site, which spans the acidic domain I, is necessary for the formation of the sixth complex only. In contrast, P(IND) does not form the sixth complex when interacted with homologous N protein. Interestingly, P(NJ) forms only complexes 1 to 5 when it interacts with N(IND). The above results suggest that the complex 6 formation or domain I interacting site is NJ-serotype specific. Two chimeric P proteins were made using heterologous domains I and II/III of the P proteins of both serotypes. The soluble interaction of the chimeric proteins with the N protein supported the observed serotype specific interactions. The chimeric P proteins bound with equal efficiency with N-RNA template of both serotypes. These results strongly suggest that the acidic domain I of the P protein differentially interacts with homologous and heterologous N proteins. The biological significance of these findings is discussed.
...
PMID:Acidic domain of the phosphoprotein (P) of vesicular stomatitis virus differentially interacts with homologous and heterologous nucleocapsid protein (N). 822 May 88
Specific interaction between the nucleocapsid protein (N) and the
phosphoprotein
(P) of vesicular
stomatitis
virus (VSV), an important step in the life-cycle of the virus, was studied by using a two-hybrid system. Plasmids encoding P fused with the yeast GAL4 DNA-binding domain (pGALP) and N fused with the herpes simplex virus VP16 transactivating region (pVPN) were transfected into CHO cells along with a reporter plasmid encoding chloramphenicol acetyltransferase (CAT). The ability of N and P to associate in vivo was measured by activation of the CAT gene by the VP16 transactivating region. Transfection of plasmids pGALP and pVPN resulted in a high level of CAT activity, indicating that the N and P portions of the fusion proteins associated very strongly with each other. Progressive C-terminal deletions of the P protein revealed two regions that are important for association with the N protein: the N-terminal acidic domain and the C-terminal basic domain. Phosphorylation of P protein was not required for N-P association. Various deletions and mutations of the N protein revealed the C-terminal 5 amino acids (Val-Glu-Phe-Asp-Lys), in particular the amino acids Val-Glu-Phe, to be critical for N association with P. This two-hybrid system can be used in other viral systems to study the interaction between proteins involved in transcription and replication.
...
PMID:Mapping of interacting domains between the nucleocapsid protein and the phosphoprotein of vesicular stomatitis virus by using a two-hybrid system. 823 1
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