herbimycin has been researched along with Astrocytoma* in 1 studies
1 other study(ies) available for herbimycin and Astrocytoma
| Article | Year |
|---|---|
Secretory phospholipase A2 induces phospholipase Cgamma-1 activation and Ca2+ mobilization in the human astrocytoma cell line 1321N1 by a mechanism independent of its catalytic activity.
The effect of secretory phospholipase A2 (sPLA2) on intracellular Ca2+ signaling in human astrocytoma cells was studied. sPLA2 increased cytosolic [Ca2+] ([Ca2+]c) in both Ca2+-containing and Ca2+-free medium, thus suggesting Ca2+ release from intracellular stores. The activation by sPLA2 of arachidonate release via cytosolic PLA2 (cPLA2) was also independent of extracellular Ca2+. As sPLA2 requires Ca2+ for activity, these results indicate that both Ca2+ mobilization and cPLA2 activation induced by sPLA2 are unrelated to phospholipase activity but dependent on signaling mechanisms. The sPLA2-induced [Ca2+]c peak was sensitive to Bordetella pertussis toxin and inhibited by caffeine, suggesting its mediation by inositol 1,4,5-trisphosphate (IP3). sPLA2 induced tyrosine phosphorylation and membrane targeting of phospholipase Cgamma-1 (PLCgamma-1). Moreover, the Ca2+ peak was sensitive to protein tyrosine kinase inhibitors. sPLA2 activates two signaling pathways: one leading to the activation of the MAP kinase/cPLA2 cascade and another leading to PLCgamma activation and Ca2+ release. Topics: Astrocytoma; Benzoquinones; Caffeine; Calcium; Calcium-Calmodulin-Dependent Protein Kinases; Catalysis; Enzyme Inhibitors; Humans; Isoenzymes; Lactams, Macrocyclic; Models, Biological; Pertussis Toxin; Phosphodiesterase Inhibitors; Phospholipase C gamma; Phospholipases A; Phospholipases A2; Phosphorylation; Quinones; Rifabutin; Signal Transduction; Time Factors; Tumor Cells, Cultured; Type C Phospholipases; Tyrosine; Virulence Factors, Bordetella | 1999 |