Caspase‐2 is resistant to inhibition by inhibitor of apoptosis proteins (IAPs) and can activate caspase‐7

• Published in: The FEBS journal Vol. 272; no. 6; pp. 1401 - 1414
• Main Authors: Ho, Po‐ki, Jabbour, Anissa M., Ekert, Paul G., Hawkins, Christine J.
• Format: Journal Article
• Language: English
• Published: Oxford, UK Blackwell Science Ltd 01.03.2005; Blackwell Publishing Ltd
• Subjects: Animals; Apoptosis - physiology; Caspase 2; Caspase 7; Caspase Inhibitors; Caspases - metabolism; Cytokines; Enzyme Activation; enzyme activity; Inhibitor of Apoptosis Proteins; Mammals; protease; Proteins; Proteins - metabolism; Recombinant Proteins - metabolism; S. cerevisiae; Saccharomyces cerevisiae - genetics; Saccharomyces cerevisiae - metabolism; Signal Transduction; Yeast
• ISSN: 1742-464X; 1742-4658
• DOI: 10.1111/j.1742-4658.2005.04573.x

Caspases are a family of cysteine proteases with roles in cytokine maturation or apoptosis. Caspase‐2 was the first pro‐apoptotic caspase identified, but its functions in apoptotic signal transduction are still being elucidated. This study examined the regulation of the activity of caspase‐2 using recombinant proteins and a yeast‐based system. Our data suggest that for human caspase‐2 to be active its large and small subunits must be separated. For maximal activity its prodomain must also be removed. Consistent with its proposed identity as an upstream caspase, caspase‐2 could provoke the activation of caspase‐7. Caspase‐2 was not subject to inhibition by members of the IAP family of apoptosis inhibitors.