scholarly journals Synthesis of Vesicular Stomatitis Virus Negative-Strand RNA In Vitro: Dependence on Viral Protein Synthesis

1982 ◽  
Vol 41 (3) ◽  
pp. 821-832 ◽  
Author(s):  
Nancy L. Davis ◽  
Gail W. Wertz
Keyword(s):  
Protein Synthesis ◽  
Vesicular Stomatitis Virus ◽  
Viral Protein ◽  
Viral Protein Synthesis ◽  
Negative Strand ◽  
Vesicular Stomatitis

scholarly journals Studies on the mechanism for entry of vesicular stomatitis virus glycoprotein g mRNA into membrane-bound polyribosome complexes

1977 ◽  
Vol 74 (1) ◽  
pp. 43-57 ◽  
Author(s):  
MJ Grubman ◽  
JA Weinstein ◽  
DA Shafritz
Keyword(s):  
Protein Synthesis ◽  
Vesicular Stomatitis Virus ◽  
Cytosol Fraction ◽  
Initial Event ◽  
Glycoprotein G ◽  
Nonspecific Effects ◽  
Membrane Bound ◽  
Vesicular Stomatitis

Glycoprotein mRNA (G mRNA) of vesicular stomatitis virus is synthesized in the cytosol fraction of infected HeLa cells. Shortly after synthesis, this mRNA associates with 40S ribosomal subunits and subsequently forms 80S monosomes in the cytosol fraction. The bulk of labeled G mRNA is then found in polysomes associated with the membrane, without first appearing in the subunit or monomer pool of the membrane-bound fraction. Inhibition of the initiation of protein synthesis by pactamycin or muconomycin A blocks entry of newly synthesized G m RNA into membrane-bound polysomes. Under these circumstances, labeled G mRNA accumulates into the cytosol. Inhibition of the elongation of protein synthesis by cucloheximide, however, allows entry of 60 percent of newly synthesized G mRNA into membrane-bound polysomes. Furthermore, prelabeled G mRNA associated with membrane-bound polysomes is released from the membrane fraction in vivo by pactamycin or mucomycon A and in vitro by 1mM puromycin - 0.5 M KCI. This release is not due to nonspecific effects of the drugs. These results demonstrate that association of G mRNA with membrane-bound polysomes is dependent upon polysome formation and initiation of protein synthesis. Therefore, direct association of the 3' end of G mRNA with the membrane does not appear to be the initial event in the formation of membrane-bound polysomes.

scholarly journals Replication and Cytopathic Effect of Oncolytic Vesicular Stomatitis Virus in Hypoxic Tumor Cells In Vitro and In Vivo

2004 ◽  
Vol 78 (17) ◽  
pp. 8960-8970 ◽  
Author(s):  
John H. Connor ◽  
Christine Naczki ◽  
Costas Koumenis ◽  
Douglas S. Lyles
Keyword(s):  
Protein Synthesis ◽  
Vesicular Stomatitis Virus ◽  
Viral Protein ◽  
Translation Initiation Factor ◽  
Initiation Factor ◽  
Progeny Virus ◽  
Hypoxic Stress ◽  
Α Subunit ◽  
Hypoxic Conditions ◽  
Vesicular Stomatitis

ABSTRACT Tumor hypoxia presents an obstacle to the effectiveness of most antitumor therapies, including treatment with oncolytic viruses. In particular, an oncolytic virus must be resistant to the inhibition of DNA, RNA, and protein synthesis that occurs during hypoxic stress. Here we show that vesicular stomatitis virus (VSV), an oncolytic RNA virus, is capable of replication under hypoxic conditions. In cells undergoing hypoxic stress, VSV infection produced larger amounts of mRNA than under normoxic conditions. However, translation of these mRNAs was reduced at earlier times postinfection in hypoxia-adapted cells than in normoxic cells. At later times postinfection, VSV overcame a hypoxia-associated increase in α subunit of eukaryotic initiation factor 2 (eIF-2α) phosphorylation and initial suppression of viral protein synthesis in hypoxic cells to produce large amounts of viral protein. VSV infection caused the dephosphorylation of the translation initiation factor eIF-4E and inhibited host translation similarly under both normoxic and hypoxic conditions. VSV produced progeny virus to similar levels in hypoxic and normoxic cells and showed the ability to expand from an initial infection of 1% of hypoxic cells to spread through an entire population. In all cases, virus infection induced classical cytopathic effects and apoptotic cell death. When VSV was used to treat tumors established in nude mice, we found VSV replication in hypoxic areas of these tumors. This occurred whether the virus was administered intratumorally or intravenously. These results show for the first time that VSV has an inherent capacity for infecting and killing hypoxic cancer cells. This ability could represent a critical advantage over existing therapies in treating established tumors.

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 Cleavage of Poly(A)-Binding Protein by Coxsackievirus 2A Protease In Vitro and In Vivo: Another Mechanism for Host Protein Synthesis Shutoff?

1999 ◽  
Vol 73 (1) ◽  
pp. 709-717 ◽  
Author(s):  
Vaishali Kerekatte ◽  
Brett D. Keiper ◽  
Cornel Badorff ◽  
Aili Cai ◽  
Kirk U. Knowlton ◽  
...  
Keyword(s):  
Protein Synthesis ◽  
Translation Initiation ◽  
Viral Protein ◽  
Binding Protein ◽  
Host Protein ◽  
Viral Protein Synthesis ◽  
2A Protease ◽  
Host Protein Synthesis

ABSTRACT Infection of cells by picornaviruses of the rhinovirus, aphthovirus, and enterovirus groups results in the shutoff of host protein synthesis but allows viral protein synthesis to proceed. Although considerable evidence suggests that this shutoff is mediated by the cleavage of eukaryotic translation initiation factor eIF4G by sequence-specific viral proteases (2A protease in the case of coxsackievirus), several experimental observations are at variance with this view. Thus, the cleavage of other cellular proteins could contribute to the shutoff of host protein synthesis and stimulation of viral protein synthesis. Recent evidence indicates that the highly conserved 70-kDa cytoplasmic poly(A)-binding protein (PABP) participates directly in translation initiation. We have now found that PABP is also proteolytically cleaved during coxsackievirus infection of HeLa cells. The cleavage of PABP correlated better over time with the host translational shutoff and onset of viral protein synthesis than did the cleavage of eIF4G. In vitro experiments with purified rabbit PABP and recombinant human PABP as well as in vivo experiments withXenopus oocytes and recombinant Xenopus PABP demonstrate that the cleavage is catalyzed by 2A protease directly. N- and C-terminal sequencing indicates that cleavage occurs uniquely in human PABP at482VANTSTQTM↓GPRPAAAAAA500, separating the four N-terminal RNA recognition motifs (80%) from the C-terminal homodimerization domain (20%). The N-terminal cleavage product of PABP is less efficient than full-length PABP in restoring translation to a PABP-dependent rabbit reticulocyte lysate translation system. These results suggest that the cleavage of PABP may be another mechanism by which picornaviruses alter the rate and spectrum of protein synthesis.

scholarly journals Natural killer T cell immunotherapy combined with oncolytic vesicular stomatitis virus or reovirus treatments differentially increases survival in mouse models of ovarian and breast cancer metastasis

2021 ◽  
Vol 9 (3) ◽  
pp. e002096
Author(s):  
Simon Gebremeskel ◽  
Adam Nelson ◽  
Brynn Walker ◽  
Tora Oliphant ◽  
Lynnea Lobert ◽  
...  
Keyword(s):  
Breast Cancer ◽  
Vesicular Stomatitis Virus ◽  
Cell Activation ◽  
Tumor Burden ◽  
Oncolytic Viruses ◽  
Nkt Cell ◽  
Cell Immunotherapy ◽  
Vesicular Stomatitis ◽  
Better Than

BackgroundOncolytic viruses reduce tumor burden in animal models and have generated promising results in clinical trials. However, it is likely that oncolytic viruses will be more effective when used in combination with other therapies. Current therapeutic approaches, including chemotherapeutics, come with dose-limiting toxicities. Another option is to combine oncolytic viruses with immunotherapeutic approaches.MethodsUsing experimental models of metastatic 4T1 breast cancer and ID8 ovarian peritoneal carcinomatosis, we examined natural killer T (NKT) cell-based immunotherapy in combination with recombinant oncolytic vesicular stomatitis virus (VSV) or reovirus. 4T1 mammary carcinoma cells or ID8 ovarian cancer cells were injected into syngeneic mice. Tumor-bearing mice were treated with VSV or reovirus followed by activation of NKT cells via the intravenous administration of autologous dendritic cells loaded with the glycolipid antigen α-galactosylceramide. The effects of VSV and reovirus on immunogenic cell death (ICD), cell viability and immunogenicity were tested in vitro.ResultsVSV or reovirus treatments followed by NKT cell activation mediated greater survival in the ID8 model than individual therapies. The regimen was less effective when the treatment order was reversed, delivering virus treatments after NKT cell activation. In the 4T1 model, VSV combined with NKT cell activation increased overall survival and decreased metastatic burden better than individual treatments. In contrast, reovirus was not effective on its own or in combination with NKT cell activation. In vitro, VSV killed a panel of tumor lines better than reovirus. VSV infection also elicited greater increases in mRNA transcripts for proinflammatory cytokines, chemokines, and antigen presentation machinery compared with reovirus. Oncolytic VSV also induced the key hallmarks of ICD (calreticulin mobilization, plus release of ATP and HMGB1), while reovirus only mobilized calreticulin.ConclusionTaken together, these results demonstrate that oncolytic VSV and NKT cell immunotherapy can be effectively combined to decrease tumor burden in models of metastatic breast and ovarian cancers. Oncolytic VSV and reovirus induced differential responses in our models which may relate to differences in virus activity or tumor susceptibility.

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