Wortmannin enhances activation of CPP32 (Caspase-3) induced by TNF or anti-Fas.
CPP32/apopain (Caspase-3), a protease of the Ced-3/ICE family, is a central mediator in the apoptosis induced by TNF or anti-Fas. In this study we demonstrate that wortmannin, an inhibitor of PI-3K, enhances the activation of CPP32 (Caspase-3) and DNA fragmentation in TNF-treated U937 cells and anti-Fas-treated Jurkat cells. Caspase-3-like activity, Ac-DEVD-MCA cleavage activity, is enhanced by wortmannin in the range of the concentration (1 - 100 nM) specifically inhibiting PI-3K. LY294002, another PI-3K inhibitor, also enhances Caspase-3-like activity, but inhibitors for myosin light chain kinase and calmodulin dependent kinase do not have any effect on the Caspase-3-like activity. Wortmannin (1 - 100 nM) enhances the processing of Caspase-3 (32K) into active form (17K) in TNF- or anti-Fas-treated cells, but not in untreated cells. These observations suggest that inhibition of PI-3K induces the activation of processing enzyme of Caspase-3 or increases the susceptibility of Caspase-3 to the processing enzyme. PI-3K seems to protect the cells from apoptosis by suppressing the activation of Caspase-3.
Fujita
E
E
Division of Development and Differentiation, National Institute of Neuroscience, NCNP, Kodaira, Tokyo 187, Japan.
Kouroku
Y
Y
Miho
Y
Y
Tsukahara
T
T
Ishiura
S
S
Momoi
T
T
D000730:Androstadienes / Q000494:pharmacology*; D000906:Antibodies / Q000494:pharmacology; D017209:Apoptosis / Q000187:drug effects / Q000502:physiology; D001483:Base Sequence; D020170:Caspase 1 / Q000378:metabolism; D053148:Caspase 3; D020169:Caspases / Q000235:genetics / Q000378:metabolism*; D003374:Coumarins / Q000378:metabolism; D053938:DNA Fragmentation / Q000187:drug effects; D017931:DNA Primers / Q000235:genetics; D004789:Enzyme Activation / Q000187:drug effects; D004791:Enzyme Inhibitors / Q000494:pharmacology; D006801:Humans; D019169:Jurkat Cells; D009842:Oligopeptides / Q000378:metabolism; D000081082:Phosphoinositide-3 Kinase Inhibitors; D011065:Poly(ADP-ribose) Polymerases / Q000378:metabolism; D014409:Tumor Necrosis Factor-alpha / Q000494:pharmacology*; D020298:U937 Cells; D000077191:Wortmannin; D019014:fas Receptor / Q000378:metabolism*
C112287:Ac-aspartyl-glutamyl-valyl-aspartyl-aminomethylcoumarin; D000730:Androstadienes; D000906:Antibodies; D003374:Coumarins; D017931:DNA Primers; D004791:Enzyme Inhibitors; D009842:Oligopeptides; D000081082:Phosphoinositide-3 Kinase Inhibitors; D014409:Tumor Necrosis Factor-alpha; D019014:fas Receptor; D011065:Poly(ADP-ribose) Polymerases; C505407:CASP3 protein, human; D053148:Caspase 3; D020169:Caspases; D020170:Caspase 1; D000077191:Wortmannin