title: Implication of phospholipase D2 in oxidant-induced phosphoinositide 3-kinase signaling via Pyk2 activation in PC12 cells.
abstract: The role of phospholipase D (PLD) activation in hydrogen peroxide (H(2)O(2))-induced signal transduction and cellular responses is not completely understood. Here we present evidence that Ca(2+)-dependent tyrosine kinase, Pyk2, requires PLD activation to mediate survival pathways in rat pheochromocytoma PC12 cells under oxidative stress. The H(2)O(2)-induced phosphorylation of two Pyk2 sites (Tyr(580), and Tyr(881)) was suppressed by 1-butanol, an inhibitor of transphosphatidylation by PLD, and also by transfection of catalytically negative mouse PLD2K758R (PLD2KR). Furthermore, we found that PLD2 was associated with Pyk2 and Src, and that activation of PLD2 was required for H(2)O(2)-enhanced association of Src with Pyk2 leading to full activation of Pyk2. H(2)O(2)-induced phosphorylation of Akt and p70S6K was dependent on phosphatidylinositol 3-kinase (PI3K) activity and was abolished by 1-butanol but not t-butanol. Furthermore, the PI3K/Akt activation in response to H(2)O(2) was reduced by transfection of either PLD2KR or the dominant negative Pyk2DN. This study is the first demonstration that PLD2 activation is implicated in Src-dependent phosphorylation of Pyk2 (Tyr(580) and Tyr(881)) by promoting the complex formation between Pyk2 and activated Src in PC12 cells exposed to H(2)O(2), thereby resulting in activation of the survival signaling pathway PI3K/Akt/p70S6K.
authors.affiliation: Department of Cell Signaling, Gifu University Graduate School of Medicine, Gifu 501-1194, Japan. banno@cc.gifu-u.ac.jp
authors.forename: Yoshiko
authors.initials: Y
authors.lastname: Banno
authors.forename: Kenji
authors.initials: K
authors.lastname: Ohguchi
authors.forename: Naoki
authors.initials: N
authors.lastname: Matsumoto
authors.forename: Masahiro
authors.initials: M
authors.lastname: Koda
authors.forename: Masashi
authors.initials: M
authors.lastname: Ueda
authors.forename: Akira
authors.initials: A
authors.lastname: Hara
authors.forename: Ivan
authors.initials: I
authors.lastname: Dikic
authors.forename: Yoshinori
authors.initials: Y
authors.lastname: Nozawa
mesh_terms: D000818:Animals; D004815:Epidermal Growth Factor / Q000378:metabolism; D051418:Focal Adhesion Kinase 2; D006861:Hydrogen Peroxide / Q000378:metabolism; D016877:Oxidants / Q000494:pharmacology*; D016716:PC12 Cells; D019869:Phosphatidylinositol 3-Kinases / Q000378:metabolism*; D010739:Phospholipase D / Q000378:metabolism*; D010766:Phosphorylation; D017346:Protein Serine-Threonine Kinases / Q000378:metabolism; D011505:Protein-Tyrosine Kinases / Q000378:metabolism*; D011518:Proto-Oncogene Proteins / Q000378:metabolism; D051057:Proto-Oncogene Proteins c-akt; D051381:Rats; D015398:Signal Transduction / Q000187:drug effects / Q000502:physiology*; D019061:src-Family Kinases / Q000378:metabolism
chemical_list: D004815:Epidermal Growth Factor; D051418:Focal Adhesion Kinase 2; D006861:Hydrogen Peroxide; D016877:Oxidants; D019869:Phosphatidylinositol 3-Kinases; D010739:Phospholipase D; D017346:Protein Serine-Threonine Kinases; D011505:Protein-Tyrosine Kinases; D011518:Proto-Oncogene Proteins; D051057:Proto-Oncogene Proteins c-akt; D019061:src-Family Kinases; C496054:Ptk2b protein, rat; C494920:Akt1 protein, rat; C105606:phospholipase D2