Caspase-9 monoclonal antibody (5B4)

Apoptosis is a major form of cell death characterized by several morphological features that include chromatin condensation and fragmentation, cell membrane blebbing, and formation of apoptotic bodies.  These morphological changes occur via signalling pathways that lead to the recruitment and activation of caspases, a family of cysteine-containing, aspartate-specific proteases.  Caspases exist as inactive proenzymes in cells, and are activated through their processing into two subunits in response to apoptotic stimulation.  Activated caspases cleave a variety of important cellular proteins, other caspases, and Bcl-2 family members, leading to a commitment to cell death.  Caspase-9, also known as ICE-LAP61, Mch-62 or Apaf-33 is a 45 kDa protein that is involved in one of the relatively well characterized caspase cascades.  It is triggered by Cytochrome C release from the mitochondria, which promotes the activation of caspase-9 by forming a complex with Apaf-1 in the presence of dATP.  Once activated, caspase-9 initiates a caspase cascade involving caspase-3, -6, and -7.  The active form of caspase-9 is composed of a 32-35 kDa subunit and 10 kDa subunit.  Caspase-9 is expressed in a variety of tissues.