title: Effect of the phosphatidylinositol 3-kinase/Akt pathway on influenza A virus propagation.
abstract: The phosphatidylinositol 3-kinase (PI3K)/Akt signalling pathway has attracted much recent interest due to its central role in modulating diverse downstream signalling pathways associated with cell survival, proliferation, differentiation, morphology and apoptosis. An increasing amount of information has demonstrated that many viruses activate the PI3K/Akt pathway to augment their efficient replication. In this study, the effect of the PI3K/Akt signalling pathway on influenza virus propagation was investigated. It was found that Akt phosphorylation was elevated in the late phase of influenza A/PR/8/34 infection in human lung carcinoma cells (A549). The PI3K-specific inhibitor LY294002 could suppress Akt phosphorylation, suggesting that influenza A virus-induced Akt phosphorylation is PI3K-dependent. UV-irradiated influenza virus failed to induce Akt phosphorylation, indicating that viral attachment and entry were not sufficient to trigger PI3K/Akt pathway activation. Blockage of PI3K/Akt activation by LY294002 and overexpression of the general receptor for phosphoinositides-1 PH domain (Grp1-PH) led to a reduction in virus yield. Moreover, in the presence of LY294002, viral RNA synthesis and viral protein expression were suppressed and, possibly as a consequence of low NP and M1 protein level, viral RNP nuclear export was also suppressed. These data suggest that the PI3K/Akt signalling pathway plays a role in influenza virus propagation.
authors.affiliation: Vaccine and Infectious Disease Organization, University of Saskatchewan, Saskatoon, SK S7N 5E3, Canada.
authors.forename: Yeun-Kyung
authors.initials: YK
authors.lastname: Shin
authors.affiliation: Vaccine and Infectious Disease Organization, University of Saskatchewan, Saskatoon, SK S7N 5E3, Canada.
authors.forename: Qiang
authors.initials: Q
authors.lastname: Liu
authors.affiliation: Vaccine and Infectious Disease Organization, University of Saskatchewan, Saskatoon, SK S7N 5E3, Canada.
authors.forename: Suresh K
authors.initials: SK
authors.lastname: Tikoo
authors.affiliation: Vaccine and Infectious Disease Organization, University of Saskatchewan, Saskatoon, SK S7N 5E3, Canada.
authors.forename: Lorne A
authors.initials: LA
authors.lastname: Babiuk
authors.affiliation: Vaccine and Infectious Disease Organization, University of Saskatchewan, Saskatoon, SK S7N 5E3, Canada.
authors.forename: Yan
authors.initials: Y
authors.lastname: Zhou
mesh_terms: D015153:Blotting, Western; D045744:Cell Line, Tumor; D002467:Cell Nucleus / Q000378:metabolism; D002470:Cell Survival; D002867:Chromones / Q000494:pharmacology; D004791:Enzyme Inhibitors / Q000494:pharmacology; D006384:Hemagglutination; D006801:Humans; D009980:Influenza A virus / Q000502:physiology*; D008856:Microscopy, Fluorescence; D009025:Morpholines / Q000494:pharmacology; D019869:Phosphatidylinositol 3-Kinases / Q000378:metabolism*; D000081082:Phosphoinositide-3 Kinase Inhibitors; D010766:Phosphorylation; D051057:Proto-Oncogene Proteins c-akt / Q000378:metabolism*; D012367:RNA, Viral / Q000096:biosynthesis; D020133:Reverse Transcriptase Polymerase Chain Reaction; D012261:Ribonucleoproteins / Q000378:metabolism; D015398:Signal Transduction; D014764:Viral Proteins / Q000096:biosynthesis; D014779:Virus Replication / Q000187:drug effects
chemical_list: D002867:Chromones; D004791:Enzyme Inhibitors; D009025:Morpholines; D019869:Phosphatidylinositol 3-Kinases; D000081082:Phosphoinositide-3 Kinase Inhibitors; D051057:Proto-Oncogene Proteins c-akt; D012367:RNA, Viral; D012261:Ribonucleoproteins; D014764:Viral Proteins; C085911:2-(4-morpholinyl)-8-phenyl-4H-1-benzopyran-4-one