From: Cell Cycle Exit: Growth Arrest, Apoptosis, and Tumor Suppression Revisited
 | Ligands | Receptors | Adaptors | First-level Caspases | Regulators | Second-level Caspases | Nucleases | |||
---|---|---|---|---|---|---|---|---|---|---|
Inhibitors | Activators | |||||||||
Humans | FAS-ligand | CD95/APO-1/FAS | FADD | Caspase-8 | Bcl2 | Â | Bax | Apaf-1 | Caspase-3 | CAD |
 | TNF? | TNF-R1 | TRADD | Caspase-10 | Bcl-X L |  | Bik |  |  |  |
C. elegans | ? | ? | ? | ? | Â | ced-9 | Â | ced-4 | ced-3 | ? |