Vanadate-induced activation of cytosolic phospholipase A2alpha in L929 cells: Roles of tyrosine kinase, protein kinase C, and extracellular signal-regulated kinase.

  title={Vanadate-induced activation of cytosolic phospholipase A2alpha in L929 cells: Roles of tyrosine kinase, protein kinase C, and extracellular signal-regulated kinase.},
  author={Tomoko Taniguchi and Masaya Shimizu and Hiroyuki Nakamura and Tetsuya Hirabayashi and Hiromichi Fujino and Takeshi Saito and Toshihiko Murayama},
  journal={Biochemical pharmacology},
  volume={73 6},
Orthovanadate (Na3VO4), which acts as an inhibitor of protein tyrosine phosphatases, has a various pharmacological effects including the release of arachidonic acid (AA) from cells. We investigated roles of alpha-type cytosolic phospholipase A2 (cPLA2alpha), Src family kinases (Src) and protein kinase C (PKC) in the release of AA induced by Na3VO4 from a murine fibroblast cell line, L929. C12 cells, a variant of L929 that lacks expression of cPLA2alpha, were used along with a clone of C12 cells… 
Activation of cytosolic phospholipase A2alpha by epidermal growth factor (EGF) and phorbol ester in HeLa cells: different effects of inhibitors for EGF receptor, protein kinase C, Src, and C-Raf.
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Effects of ceramide, ceramidase inhibition and expression of ceramide kinase on cytosolic phospholipase A2alpha; additional role of ceramide-1-phosphate in phosphorylation and Ca2+ signaling.
The findings suggest that C1P is a stimulatory factor on cPLA(2)alpha that is independent of the Ca(2+) signal and the PKC-ERK-mediated phosphorylation signal.
Regulation of alkaline ceramidase activity by the c-Src-mediated pathway.
The data suggest that c-Src-mediated signal positively regulates ACER activity in a Ca(2+)-independent manner, and the ceramidase sensitivity to substrates, pH, and Ca( 2+) suggest that the c- Src- and SU6656-sensitive ceramodase is alkaline ceramidsase (ACER), possibly Ca(1+)-activated ACER2.
Activation of ceramidase and ceramide kinase by vanadate via a tyrosine kinase-mediated pathway.
The improved thin-layer chromatography method was useful for the simultaneous determination of enzymatic activities for ceramide metabolism in cells and determined levels of C1P, caproic acid, sphingomyelin, and glucosylceramide simultaneously.
Effects of Hsp 90 inhibitors , geldanamycin and its analog , on ceramide metabolism and cytotoxicity in PC 12 cells
The inhibitors of heat shock protein-90 (Hsp90), geldanamycin (GA) and 17-(allylamino)17-desmethoxygeldanamycin, show various cellular effects including destabilization of Hsp90 clients and
Effects of Hsp90 inhibitors, geldanamycin and its analog, on ceramide metabolism and cytotoxicity in PC12 cells.
The results suggest the possible involvement of ceramide metabolism, not AA release, in GA-induced cytotoxicity in PC12 cells.


Expression of cytosolic phospholipase A2 alpha in murine C12 cells, a variant of L929 cells, induces arachidonic acid release in response to phorbol myristate acetate and Ca2+ ionophores, but not to tumor necrosis factor-alpha.
Results suggest that C12 cells may lack the components necessary for TNFalpha-induced AA release, in addition to cPLA2alpha, and the role of Ser505 phosphorylation in AA release induced by PMA is discussed.
Ceramide-1-phosphate activates cytosolic phospholipase A2alpha directly and by PKC pathway.
It is proposed that C1P stimulates AA release via two mechanisms; direct activation of cPLA2alpha, and the PKC-dependent pathway.
Phospholipase A2 Is Necessary for Tumor Necrosis Factor α-induced Ceramide Generation in L929 Cells*
The introduction of the cPLA2 gene into C12 cells resulted in partial restoration of TNFα-induced arachidonate release, ceramide accumulation, and cytotoxicity, suggesting that c PLA2 is a necessary component in the pathways leading to ceramic accumulation and cell death.
Regulatory mechanism and physiological role of cytosolic phospholipase A2.
This review discusses the essential features of cPLA2alpha regulation and addresses new insights into the functional properties of this enzyme, which has been implicated in fertility, striated muscle growth, renal concentration, postischemic brain injury, arthritis, inflammatory bone resorption, intestinal polyposis, pulmonary fibrosis, acute respiratory distress syndrome, and autoimmune encephalomyelitis.
Enhancement of arachidonic acid release and prostaglandin F(2alpha) formation by Na3VO4 in PC12 cells and GH3 cells.
Findings suggest that the tyrosine phosphorylation pathway regulates arachidonic acid release by phospholipase A2 and prostaglandin F(2alpha) formation in neuronal cells.
Phospholipase D is involved in oxidative stress-induced migration of vascular smooth muscle cells via tyrosine phosphorylation and protein kinase C
Results suggest that PLD might be involved in oxidative stress-induced migration of VSMCs, possibly via tyrosine phosphorylation and PKC activation.
Oxidative Stress Induces Protein Kinase D Activation in Intact Cells
Oxidative stress activates PKD by initiating distinct Src-dependent and -independent pathways involving PKC, suggesting that whereas Src mediates part of its effects via phospholipase C activation, PKC acts more proximally as an upstream activator of PKD.
TNF-mediated cytotoxicity of L929 cells: role of staurosporine in enhancement of cytotoxicity and translocation of protein kinase C isozymes.
The possibility that the mechanism by which staurosporine potentiates TNF action does not involve inhibition ofPKC, but in contrast may involve modulation of PKC-zeta is suggested.
Src Tyrosine Kinase Inhibitor PP2 Markedly Enhances Ras-independent Activation of Raf-1 Protein Kinase by Phorbol Myristate Acetate and H2O2*
PP2 effect resulted in significant and sustained Ras-independent activation of Raf-1 by PMA and H2O2, and suggests that a tyrosine phosphorylation event is involved in the negative feedback regulation of Rafael-1.