Protein synthesis in vaccinia virus-infected cells

Abstract

Human Hep-2 cells were submitted to hypertonic shock (210 mM NaCl) to block host protein synthesis before infection with vaccinia virus. With the start of infection, the medium isotonicity (116 mM NaCl) was restored, and the effect of viral infection on the recovery of host polyribosomes and protein synthesis was studied. Although host translation blockage was released together with infection, vaccinia virus did not affect immediately host protein synthesis. During the first hour of recovery, infected cells could perfectly rebuild the polyribosome profile and recuperate the rate of protein synthesis. Also, during recovery, formation of the initiation complex for protein synthesis was not affected by viral infection. In this period, viral mRNA and proteins were detected by slot blot and SDS-polyacrylamide gel electrophoresis. The inhibitory effect of vaccinia virus on host translation was observed after the second hour of infection. These findings suggest that vaccinia virus-mediated shutoff occurs in a later period during infection, in parallel with viral mRNA accumulation in the polyribosomes and after the on-set of viral DNA replication.

Redistribution of Cyclophilin A to Viral Factories during Vaccinia Virus Infection and Its Incorporation into Mature Particles

“…In this study, we have focused on this issue and evaluated the expression pattern and intracellular distribution of CypA during VV infection. CypA synthesis is completely blocked at late times of the VV replicative cycle, which is consistent with the overall shutoff of host translation induced by VV infection, as described by others (17,41). Despite that, CypA accumulation is sustained throughout infection.…”

“…1C). This result was not totally unexpected because infection of cells with VV is known to induce a severe shutoff of host protein synthesis (17,41). This effect is observed in Fig.…”

Biological Characterization and Next-Generation Genome Sequencing of the Unclassified Cotia Virus SPAn232 (Poxviridae)

“…Interestingly, although we observed the inhibition of cellular protein synthesis as infection developed (Fig. 3C, asterisks), this effect was not as dramatic as the typical shutoff of host translation observed during infection with VACV (9,22).…”

“…Cells were then harvested in sodium dodecyl sulfate (SDS) sample buffer, and samples were subjected to electrophoresis in a 12% SDS-polyacrylamide gel electrophoresis (PAGE) gel, as described previously (22). The gels were dried and exposed to X-ray films.…”

Cyclosporin A inhibits vaccinia virus replication in vitro

“…4. After each labeling period, cells were prepared for electrophoresis as described elsewhere [9]. Samples were analyzed on a 12~o sodium dodecyl sulfate (SDS)-polyacrilamide gels using the buffer system described by Laemmli [22].…”