Mitochondria play key roles in activating apoptosis in mammalian cells. The mitochondrial stage of apoptosis control is regulated by the Bcl-2 family of proteins.  Bcl-2 family members mediate the release of proteins, for example, cytochrome c, from the space between the inner and outer mitochondrial membranes to the cytosol results in activation of caspase, which play essential role in programmed cell death. 
Signosis has developed a plate-based array for profiling 20+ Mitochondria Apoptosis-regulated genes. By using this assay, researchers are able to compare gene expression in up to three samples on a single microtiter plate.