Caspases are a family of cysteine-aspartic acid proteases that are responsible for the initiation and execution of apoptosis. Caspase-8 is a 55 kDa protein expressed as an inactive procaspase that resides in the cytosol. Activation of Caspase-8 requires cleavage into its large (17-21 kDa) and small (10-13 kDa) catalytic subunits. Caspase-8 has been shown to play a role in the induction of apoptosis by both death receptor mediated and non-receptor mediated mechanisms (1). Caspase-8 signals to effector Caspase-3 to execute apoptosis.
