Since prior studies indicate that L2 is critical selleck kinase inhibitor for endosomal escape and targeting of the viral DNA to ND10 and that gamma secretase is located in endosomal membranes, our findings suggest that either L2 or an intracellular receptor are cleaved by gamma secretase
as papillomavirus escapes the endosome.”
“A novel assay was developed for Daudi cells in which the antiviral (AV) and antiproliferative (AP) activities of interferon (IFN) can be measured simultaneously. Using this novel assay, conditions allowing IFN AV protection but no growth inhibition were identified and selected. Daudi cells were treated under these conditions, and gene expression microarray analyses were performed. The results of the analysis identified 25 genes associated with IFN-alpha AV activity. Upregulation of 23 IFN-induced genes was confirmed by using reverse transcription-PCR. Of 25 gene products, 17
were detected by Western blotting at 24 h. Of the 25 genes, 10 have not been previously linked to AV activity of IFN-alpha. The most upregulated gene was IFIT3 (for IFN-induced protein with tetratricopeptide repeats 3). The results from antibody neutralizing experiments suggested an association of the identified genes with Rigosertib IFN-alpha AV activity. This association was strengthened by results from IFIT3-small interfering RNA transfection experiments showing decreased expression of IFIT3 and a reduction in the AV activity induced by IFN-alpha. Overexpression of IFIT3 resulted
in a decrease of virus titer. Transcription of AV genes after the treatment of cells with higher concentrations of IFN having an AP effect on Daudi cells suggested pleiotropic functions of identified gene products.”
“The African swine fever virus (ASFV) DP71L protein is present in all isolates as either a short form of 70 to 72 amino acids or a long form of about 184 amino acids, and both of these share sequence similarity to the C-terminal domain of the herpes simplex virus ICP34.5 protein and cellular protein GADD34. In the present study we expressed DP71L in different mammalian cells and demonstrated that DP71L causes dephosphorylation of eukaryotic translation initiation factor 2 alpha (eIF2 alpha) in resting cells and during chemical-induced endoplasmic reticulum stress and either acts to enhance expression of cotransfected reporter genes. We showed that DP71L binds to all the three isoforms (alpha, beta, and gamma) of the protein phosphatase 1 catalytic subunit (PP1c) and acts by recruiting PP1c to eIF2 alpha. We also showed that DP71L inhibits the induction of ATF4 and its downstream target, CHOP. We investigated the eIF2 alpha phosphorylation status and induction of CHOP in porcine macrophages infected by two ASFV field isolates, Malawi Lil20/1 and Benin 97/1, and two DP71L deletion mutants, Malawi Delta NL and E70 Delta NL.