Conditions necessary for inhibition of protein synthesis and production of cytopathic effect in Aedes albopictus cells infected with vesicular stomatitis virus

1982 ◽  
Vol 2 (1) ◽  
pp. 66-75
Author(s):  
S Gillies ◽  
V Stollar
Keyword(s):  
Protein Synthesis ◽  
Vesicular Stomatitis Virus ◽  
Aedes Albopictus ◽  
Rna Synthesis ◽  
Cytopathic Effect ◽  
Viral Gene ◽  
Inhibition Of Protein Synthesis ◽  
Infected Cells ◽  
Vesicular Stomatitis ◽  
Aedes Albopictus Cells

The relationship between the development of cytopathic effect (CPE) and the inhibition of host macromolecular synthesis was examined in a CPE-susceptible cloned line of Aedes albopictus cells after infection with vesicular stomatitis virus. To induce rapid and maximal CPE, two conditions were required: (i) presence of serum in the medium and (ii) incubation at 34 degrees C rather than at 28 degrees C. In the absence of serum, incubation of infected cultures at 34 degrees C resulted in a significant increase in viral protein and RNA synthesis compared with that observed at 28 degrees C. However, when serum was present in the medium, by 6 h after infection protein synthesis (both host and viral) was markedly inhibited when infected cells were maintained at 34 degrees C. RNA synthesis (host and viral) was also inhibited in vesicular stomatitis virus-infected cells maintained at 34 degrees C with serum, but somewhat more slowly than protein synthesis. Examination of polysome patterns indicated that when infected cultures were maintained under conditions which predispose to CPE, more than half of the ribosomes existed as monosomes, suggesting that protein synthesis was being inhibited at the level of initiation. In addition, the phosphorylation of one (or two) polysome-associated proteins was reduced when protein synthesis was inhibited. Our findings indicate a strong correlation between virus-induced CPE in the LT-C7 clone of A. albopictus cells and the inhibition of protein synthesis. Although the mechanism of the serum effect is not understood, incubation at 34 degrees C probably predisposes to CPE and inhibition of protein synthesis by increasing the amount of viral gene products made.

scholarly journals Conditions necessary for inhibition of protein synthesis and production of cytopathic effect in Aedes albopictus cells infected with vesicular stomatitis virus.

1982 ◽  
Vol 2 (1) ◽  
pp. 66-75 ◽  
Author(s):  
S Gillies ◽  
V Stollar
Keyword(s):  
Protein Synthesis ◽  
Vesicular Stomatitis Virus ◽  
Aedes Albopictus ◽  
Rna Synthesis ◽  
Cytopathic Effect ◽  
Viral Gene ◽  
Inhibition Of Protein Synthesis ◽  
Infected Cells ◽  
Vesicular Stomatitis ◽  
Aedes Albopictus Cells

The relationship between the development of cytopathic effect (CPE) and the inhibition of host macromolecular synthesis was examined in a CPE-susceptible cloned line of Aedes albopictus cells after infection with vesicular stomatitis virus. To induce rapid and maximal CPE, two conditions were required: (i) presence of serum in the medium and (ii) incubation at 34 degrees C rather than at 28 degrees C. In the absence of serum, incubation of infected cultures at 34 degrees C resulted in a significant increase in viral protein and RNA synthesis compared with that observed at 28 degrees C. However, when serum was present in the medium, by 6 h after infection protein synthesis (both host and viral) was markedly inhibited when infected cells were maintained at 34 degrees C. RNA synthesis (host and viral) was also inhibited in vesicular stomatitis virus-infected cells maintained at 34 degrees C with serum, but somewhat more slowly than protein synthesis. Examination of polysome patterns indicated that when infected cultures were maintained under conditions which predispose to CPE, more than half of the ribosomes existed as monosomes, suggesting that protein synthesis was being inhibited at the level of initiation. In addition, the phosphorylation of one (or two) polysome-associated proteins was reduced when protein synthesis was inhibited. Our findings indicate a strong correlation between virus-induced CPE in the LT-C7 clone of A. albopictus cells and the inhibition of protein synthesis. Although the mechanism of the serum effect is not understood, incubation at 34 degrees C probably predisposes to CPE and inhibition of protein synthesis by increasing the amount of viral gene products made.

Protein synthesis in lysates of Aedes albopictus cells infected with vesicular stomatitis virus

1982 ◽  
Vol 2 (10) ◽  
pp. 1174-1186
Author(s):  
S Gillies ◽  
V Stollar
Keyword(s):  
Protein Synthesis ◽  
Ribosomal Protein ◽  
Vesicular Stomatitis Virus ◽  
Aedes Albopictus ◽  
Synthetic Activity ◽  
Cell Biol ◽  
S 100 ◽  
Infected Cells ◽  
Vesicular Stomatitis ◽  
Aedes Albopictus Cells

Aedes albopictus cells (clone LT-C7) showed a marked cytopathic effect and inhibition of protein synthesis (both host and viral) after infection with vesicular stomatitis virus (VSV), but only if (i) cultures were incubated at 34 degrees C rather than 28 degrees C and (ii) serum was present in the medium (S. Gillies and V. Stollar, Mol. Cell. Biol. 2:66-75, 1982). To learn more about how protein synthesis is shut off in VSV-infected A. albopictus cells, we have compared cell-free protein synthesis in extracts prepared from VSV-infected cells and control cells. Extracts prepared 6 h after infection from VSV-infected cells maintained at 34 degrees C in the presence of serum reflected what was observed with intact cells in at least two respects: (i) they showed a markedly diminished capacity to carry out protein synthesis (whether directed by endogenous or exogenously added mRNA), and (ii) there was decreased phosphorylation in vitro by [gamma-32P]ATP of a specific ribosomal protein (Gillies and Stollar, Mol. Cell. Biol. 2:66-75, 1982). In addition, and consistent with a block at the level of initiation, the formation of 80S initiation complexes, as measured by binding of VSV 12 to 18S mRNA, was reduced in the inactive extracts. Addition of an S-100 fraction from uninfected cells to the inactive extract reversed each of the aforementioned changes; i.e., it restored protein synthetic activity, it stimulated the formation of 80S initiation complexes, and it increased phosphorylation of the specific ribosomal protein referred to above. The active component in the S-100 fraction was heat labile and non-dialyzable and, upon ammonium sulfate fractionation of the S-100 fraction, was found in the 40 to 70% saturation fraction. Our findings suggest that VSV infection of A. albopictus cells inhibits protein synthesis by inactivating a macromolecular component, probably a protein, in the S-100 fraction which may be involved in the initiation of protein synthesis. More specifically, we suggest that this component is involved in the joining of the ribosomal subunits to form 80S initiation complexes.

scholarly journals Protein synthesis in lysates of Aedes albopictus cells infected with vesicular stomatitis virus.

1982 ◽  
Vol 2 (10) ◽  
pp. 1174-1186 ◽  
Author(s):  
S Gillies ◽  
V Stollar
Keyword(s):  
Protein Synthesis ◽  
Ribosomal Protein ◽  
Vesicular Stomatitis Virus ◽  
Aedes Albopictus ◽  
Synthetic Activity ◽  
Cell Biol ◽  
S 100 ◽  
Infected Cells ◽  
Vesicular Stomatitis ◽  
Aedes Albopictus Cells

Aedes albopictus cells (clone LT-C7) showed a marked cytopathic effect and inhibition of protein synthesis (both host and viral) after infection with vesicular stomatitis virus (VSV), but only if (i) cultures were incubated at 34 degrees C rather than 28 degrees C and (ii) serum was present in the medium (S. Gillies and V. Stollar, Mol. Cell. Biol. 2:66-75, 1982). To learn more about how protein synthesis is shut off in VSV-infected A. albopictus cells, we have compared cell-free protein synthesis in extracts prepared from VSV-infected cells and control cells. Extracts prepared 6 h after infection from VSV-infected cells maintained at 34 degrees C in the presence of serum reflected what was observed with intact cells in at least two respects: (i) they showed a markedly diminished capacity to carry out protein synthesis (whether directed by endogenous or exogenously added mRNA), and (ii) there was decreased phosphorylation in vitro by [gamma-32P]ATP of a specific ribosomal protein (Gillies and Stollar, Mol. Cell. Biol. 2:66-75, 1982). In addition, and consistent with a block at the level of initiation, the formation of 80S initiation complexes, as measured by binding of VSV 12 to 18S mRNA, was reduced in the inactive extracts. Addition of an S-100 fraction from uninfected cells to the inactive extract reversed each of the aforementioned changes; i.e., it restored protein synthetic activity, it stimulated the formation of 80S initiation complexes, and it increased phosphorylation of the specific ribosomal protein referred to above. The active component in the S-100 fraction was heat labile and non-dialyzable and, upon ammonium sulfate fractionation of the S-100 fraction, was found in the 40 to 70% saturation fraction. Our findings suggest that VSV infection of A. albopictus cells inhibits protein synthesis by inactivating a macromolecular component, probably a protein, in the S-100 fraction which may be involved in the initiation of protein synthesis. More specifically, we suggest that this component is involved in the joining of the ribosomal subunits to form 80S initiation complexes.

Orobol: An Inhibitor of Vesicular Stomatitis Virus that Blocks the Synthesis of Viral Nucleic Acids and the Glycosylation of G Protein

1994 ◽  
Vol 5 (2) ◽  
pp. 99-104 ◽  
Author(s):  
M. J. Almela ◽  
A. Irurzun ◽  
L. Carrasco
Keyword(s):  
Protein Synthesis ◽  
Nucleic Acids ◽  
G Protein ◽  
Vesicular Stomatitis Virus ◽  
Viral Protein Synthesis ◽  
Viral Translation ◽  
Naturally Occurring ◽  
Infected Cells ◽  
Vesicular Stomatitis ◽  
Virus Influenza

The naturally occurring isoflavonoid orobol exhibits antiviral effects against some animal viruses. Addition of the compound after virus entry inhibits the appearance of late viral protein synthesis in Vesicular Stomatitis Virus, influenza, or vaccinia virus-infected cells, but has no effect on poliovirus protein synthesis. Concentrations of the compound above 10–50 Mg ml−1 are sufficient to decrease the synthesis of VSV proteins when added early during infection, but have no effect on viral translation if added later, indicating that orobol does not block VSV translation directly. The synthesis of VSV nucleic acids is one of the targets of this flavonoid. The synthesis of both minus and plus-stranded viral RNA are inhibited by orobol when added during the first 2 h of infection. In addition, this compound interferes potently with the glycosylation of VSV G protein, indicating that orobol has several targets of antiviral action. The possibility that orobol interferes with the function of the cellular vesicular system is discussed.

scholarly journals Structural Properties of the C Terminus of Vesicular Stomatitis Virus N Protein Dictate N-RNA Complex Assembly, Encapsidation, and RNA Synthesis

2012 ◽  
Vol 86 (16) ◽  
pp. 8720-8729 ◽  
Author(s):  
Bianca S. Heinrich ◽  
Benjamin Morin ◽  
Amal A. Rahmeh ◽  
Sean P. J. Whelan
Keyword(s):  
Gene Expression ◽  
Vesicular Stomatitis Virus ◽  
Rna Synthesis ◽  
Critical Role ◽  
Viral Gene Expression ◽  
Viral Gene ◽  
C Terminus ◽  
Vesicular Stomatitis ◽  
Rna Complex

The vesicular stomatitis virus (VSV) nucleoprotein (N) associates tightly with the viral genomic RNA. This N-RNA complex constitutes the template for the RNA-dependent RNA polymerase L, which engages the nucleocapsid via its phosphoprotein cofactor P. While N and P proteins play important roles in regulating viral gene expression, the molecular basis of this regulation remains incompletely understood. Here we show that mutations in the extreme C terminus of N cause defects in viral gene expression. To determine the underlying cause of such defects, we examined the effects of the mutations separately on encapsidation and RNA synthesis. Expression of N together with P inEscherichia coliresults predominantly in the formation of decameric N-RNA rings. In contrast, nucleocapsid complexes containing the substitution NY415Aor NK417Awere more loosely coiled, as revealed by electron microscopy (EM). In addition, the NEF419/420AAmutant was unable to encapsidate RNA. To further characterize these mutants, we engineered an infectious cDNA clone of VSV and employed N-RNA templates from those viruses to reconstitute RNA synthesisin vitro. The transcription assays revealed specific defects in polymerase utilization of the template that result in overall decreased RNA quantities, including reduced amounts of leader RNA. Passage of the recombinant viruses in cell culture led to the accumulation of compensatory second-site mutations in close proximity to the original mutations, underscoring the critical role of structural features within the C terminus in regulating N function.

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