title: PKC theta and p38 MAPK activate the EBV lytic cycle through autophagy induction.
abstract: PKC activation by combining TPA with sodium butyrate (T/B) represents the most effective and widely used strategy to induce the Epstein-Barr virus (EBV) lytic cycle. The results obtained in this study show that novel PKCθ is involved in such process and that it acts through the activation of p38 MAPK and autophagy induction. Autophagy, a mechanism of cellular defense in stressful conditions, is manipulated by EBV to enhance viral replication. Besides promoting the EBV lytic cycle, the activation of p38 and autophagy resulted in a pro-survival effect, as indicated by p38 or ATG5 knocking down experiments. However, this pro-survival role was counteracted by a pro-death activity of PKCθ, due to the dephosphorylation of AKT. In conclusion, this study reports, for the first time, that T/B activates a PKCθ-p38 MAPK axis in EBV infected B cells, that promotes the viral lytic cycle and cell survival and dephosphorylates AKT, balancing cell life and cell death.
authors.affiliation: Department of Experimental Medicine, "Sapienza" University of Rome, Italy.
authors.forename: Roberta
authors.initials: R
authors.lastname: Gonnella
authors.affiliation: Department of Experimental Medicine, "Sapienza" University of Rome, Italy.
authors.forename: Marisa
authors.initials: M
authors.lastname: Granato
authors.affiliation: Department of Experimental Medicine, "Sapienza" University of Rome, Italy.
authors.forename: Antonella
authors.initials: A
authors.lastname: Farina
authors.affiliation: Department of Experimental Medicine, "Sapienza" University of Rome, Italy.
authors.forename: Roberta
authors.initials: R
authors.lastname: Santarelli
authors.affiliation: Department of Experimental Medicine, "Sapienza" University of Rome, Italy. Electronic address: alberto.faggioni@Uniroma1.it.
authors.forename: Alberto
authors.initials: A
authors.lastname: Faggioni
authors.affiliation: Department of Experimental Medicine, "Sapienza" University of Rome, Italy. Electronic address: mara.cirone@uniroma1.it.
authors.forename: Mara
authors.initials: M
authors.lastname: Cirone
mesh_terms: D000956:Antigens, Viral / Q000378:metabolism; D001343:Autophagy / Q000187:drug effects; D001402:B-Lymphocytes / Q000187:drug effects / Q000378:metabolism / Q000821:virology; D020148:Butyric Acid / Q000494:pharmacology; D002470:Cell Survival / Q000187:drug effects; D004854:Herpesvirus 4, Human / Q000187:drug effects / Q000502:physiology*; D006801:Humans; D007527:Isoenzymes / Q000378:metabolism*; D008954:Models, Biological; D010766:Phosphorylation / Q000187:drug effects; D011493:Protein Kinase C / Q000378:metabolism*; D000074121:Protein Kinase C-theta; D051057:Proto-Oncogene Proteins c-akt / Q000037:antagonists & inhibitors / Q000378:metabolism; D015398:Signal Transduction / Q000187:drug effects; D013755:Tetradecanoylphorbol Acetate / Q000494:pharmacology; D014775:Virus Activation / Q000187:drug effects; D017735:Virus Latency / Q000187:drug effects; D048051:p38 Mitogen-Activated Protein Kinases / Q000378:metabolism*
chemical_list: D000956:Antigens, Viral; D007527:Isoenzymes; D020148:Butyric Acid; D051057:Proto-Oncogene Proteins c-akt; C076233:PRKCQ protein, human; D011493:Protein Kinase C; D000074121:Protein Kinase C-theta; D048051:p38 Mitogen-Activated Protein Kinases; D013755:Tetradecanoylphorbol Acetate
keywords: Autophagy; EBV; LC3; Lytic cycle; PKCθ; p38 MAPK