Caspases play a key role in apoptosis. Similar as other caspases, caspase-2 is also synthesized as an inactive pro-enzyme that is processed in cells undergoing apoptosis. Caspase-2 mRNA is alternatively spliced. The larger mRNA species encoding a product of 435 amino acids is known as ICH-1L. The smaller mRNA species encoding a protein of 312 amino acids is named ICH-1S. Over expression of ICH-1L induces apoptosis, while over expression of ICH-1S suppresses Rat-1 cell death induced by serum deprivation.