Cytosolic phospholipase A(2) activity during the ongoing cell cycle.
Cytosolic phospholipase A(2) (cPLA(2)) is of special interest because it selectively releases arachidonic acid from membrane phospholipids. Arachidonic acid has been implicated to play an important role in various cellular responses. Recently arachidonic acid release and prostaglandin synthesis have been shown to be cell cycle dependent and therefore the activity of cPLA(2) during the ongoing cell cycle was investigated, using the mitotic shake off method for cell synchronisation. cPLA(2) activity was high in mitotic cells and decreased rapidly in the early G1 phase. A strong increase in activity was measured following the G1/S transition in both neuroblastoma and Chinese hamster ovary cells. The changes in activity were not due to a difference in cPLA(2) expression but due to phosphorylation of cPLA(2). Phosphorylation of cPLA(2) occurs through MAPK since the use of a specific MAPK kinase inhibitor and serum depletion of synchronised cells inhibited cPLA(2) activity.
van Rossum
G S
GS
Department of Molecular Cell Biology, Institute of Biomembranes, Utrecht University, Utrecht, The Netherlands.
Vlug
A S
AS
van den Bosch
H
H
Verkleij
A J
AJ
Boonstra
J
J
D000818:Animals; D015153:Blotting, Western; D002070:Butadienes / Q000494:pharmacology; D002453:Cell Cycle / Q000502:physiology*; D002460:Cell Line; D006224:Cricetinae; D003600:Cytosol / Q000201:enzymology*; D004789:Enzyme Activation / Q000187:drug effects / Q000502:physiology; D004791:Enzyme Inhibitors / Q000494:pharmacology; D016193:G1 Phase / Q000502:physiology; D051379:Mice; D020928:Mitogen-Activated Protein Kinases / Q000037:antagonists & inhibitors / Q000378:metabolism; D008938:Mitosis / Q000502:physiology; D009570:Nitriles / Q000494:pharmacology; D010741:Phospholipases A / Q000378:metabolism*; D010766:Phosphorylation; D016196:S Phase / Q000502:physiology
D002070:Butadienes; D004791:Enzyme Inhibitors; D009570:Nitriles; C113580:U 0126; D020928:Mitogen-Activated Protein Kinases; D010741:Phospholipases A