Evidence Against the Role of K+ in the Shut-off of Protein Synthesis by Vesicular Stomatitis Virus

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.

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Valosin-Containing Protein (VCP/p97) Is a Potential Antiviral Target against Mononegavirales

Proceedings ◽

10.3390/proceedings2020050108 ◽

2020 ◽

Vol 50 (1) ◽

pp. 108

Author(s):

Victor Latorre ◽

Ron Geller

Keyword(s):

Life Cycle ◽

Respiratory Syncytial Virus ◽

Vesicular Stomatitis Virus ◽

Molecular Chaperones ◽

Cellular Machinery ◽

Vesicular Stomatitis ◽

Medical Importance ◽

Syncytial Virus ◽

Chaperone Network

The viral order Mononegavirales consist of eight virus families. Members of these families include some of the most infectious (Measles, lethal (Ebola and Rabies), and most common viruses (Respiratory syncytial virus, RSV). Despite their medical importance, few vaccines and no antiviral treatments are available for treating infections with these viruses. Being obligate cellular parasites, viruses must rely on the cellular machinery for their replication. One example of this is the widespread use of molecular chaperones, which assist the correct folding of newly synthesized proteins, refold misfolded or aggregated proteins, and play key roles in maintaining proteostasis in cells. Targeting chaperones required for viral replication may, therefore, provide an antiviral approach. In this work, we set out to identify all the members of the cytoplasmic chaperone network that are involved in the replication of RSV using an RNA interference screen. Among our hits is valosin-containing protein (VCP; also known as p97), a chaperone involved in ubiquitin-mediated protein degradation, which has been shown to play a role in the life cycle of several viruses. We investigated the role of VCP during RSV and vesicular stomatitis virus (VSV) infections using specific VCP inhibitors. Our results suggest that VCP activity is necessary for RSV and VSV replication and may constitute a promising antiviral approach for the Mononegavirales.

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Detection of buffaloes (Bubalus bubalis) seroreactive for vesicular stomatitis virus in the state of Paraíba, Northeastern Brazil

Semina Ciências Agrárias ◽

10.5433/1679-0359.2019v40n6supl3p3769 ◽

2019 ◽

Vol 40 (6Supl3) ◽

pp. 3769

Author(s):

Camila de Sousa Bezerra ◽

Jéssica Tatiane Sauthier ◽

Juliana Felipetto Cargnelutti ◽

Gisele Cândida Ramalho ◽

Denise Batista Nogueira ◽

...

Keyword(s):

Vesicular Stomatitis Virus ◽

Virus Isolation ◽

Neutralization Test ◽

Bubalus Bubalis ◽

The State ◽

Virus Neutralization Test ◽

Northeastern Brazil ◽

Antibody Titers ◽

Vesicular Stomatitis

This study aimed to determine the prevalence of vesicular stomatitis virus (VSV) in buffaloes in the state of Paraíba, Northeastern Brazil. The study was carried out in 14 herds in the municipalities of Alagoa Nova, Areia, Campina Grande, Guarabira, Juripiranga, Santa Helena, Sapê, Rio Tinto, Santana dos Garrotes, Itatuba, Solânea, and Cacimbas. The studied population was formed by buffalo females reared for meat and milk, comprising of mixed and Murrah breeds, at least 24 months of age. For the serological diagnosis of VSIV-3, the virus-neutralization test (VN) was performed, using the VSIV-3 isolate 2013 São Bento/Paraíba. Real prevalence was 2.6% for VSIV-3, with antibody titers ranging from 160 to 1280. This is the first study to characterize VSV circulation in the buffalo population in Northeastern Brazil, where infection is considered endemic; some aspects of virus maintenance are not fully understood, such as the role of reservoirs in endemic areas. The identification of seroreactive animals in this study demonstrates the circulation of VSIV-3 in the buffalo species. Reports of virus isolation in this species have not yet been described, which suggests the need for investigating the role of buffaloes in vesicular stomatitis epidemiology.

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