The 'death receptor' FAS regulates apoptosis of unwanted or dangerous cells, functioning as a guardian against autoimmunity and cancer development. Distinct cell types differ in the mechanisms by which FAS triggers apoptosis: in type I cells, FAS-induced activation of caspase-8 suffices for cell killing, whereas in type II cells there must be caspase cascade amplification. Here it is shown that the inhibitor of apoptosis XIAP is the critical factor determining this — without it, a type II cell dies in the same way as a type I cell.
- Philipp J. Jost
- Stephanie Grabow
- Thomas Kaufmann
