Activation of caspase-3 alone is insufficient for apoptotic morphological changes in human neuroblastoma cells

Autor: Songqing Na, Andrew L. Glasebrook, Neal W. Roehm, Chan Hsin S. Chang, Margaret M. Racke, Marian Mosior, Steve Kovacevic
Rok vydání: 2002
Předmět:
Zdroj: Journal of Neurochemistry. 80:1039-1048
ISSN: 0022-3042
DOI: 10.1046/j.0022-3042.2002.00787.x
Popis: Activated caspase-3 is considered an important enzyme in the cell death pathway. To study the specific role of caspase-3 activation in neuronal cells, we generated a stable tetracycline-regulated SK-N-MC neuroblastoma cell line, which expressed a highly efficient self-activating chimeric caspase-3, consisting of the caspase-1 prodomain fused to the caspase-3 catalytic domain. Under expression-inducing conditions, we observed a time-dependent increase of processed caspase-3 by immunostaining for the active form of the enzyme, intracellular caspase-3 enzyme activity, as well as poly(ADP-ribose) polymerase (PARP) cleavage. Induced expression of the caspase fusion protein showed predominantly caspase-3 activity without any apoptotic morphological changes. In contrast, staurosporine treatment of the same cells resulted in activation of multiple caspases and profound apoptotic morphology. Our work provides evidence that auto-activation of caspase-3 can be efficiently achieved with a longer prodomain and that neuronal cell apoptosis may require another caspase or activation of multiple caspase enzymes.
Databáze: OpenAIRE