Description
TNF-related apoptosis-inducing ligand (TRAIL; Apo2L;CD253; TNFSF10) is a type II transmembrane protein of about 34kDa. Like most members of the tumor necrosis factor (TNF) superfamily of cytokines TRAIL can be cleaved at the cell surface by metalloproteases to form a soluble molecule. Active TRAIL forms trimers and specifically binds to five distinct receptors: TRAIL-R1 (DR4; Apo2;CD261; TNFRSF10A), TRAIL-R2 (DR5; KILLER; TRICK2A;TRICK2B; CD262; TNFRSF10B), TRAIL-R3 (DcR1;LIT; TRID; CD263; TNFRSF10C), TRAIL-R4 (DcR2; TRUNDD; CD264; TNFRSF10D), and osteoprotegerin (OPG; OCIF; TNFRSF11B). Trimerized TRAIL triggers apoptosis upon ligation of cell surface TRAIL-R1 and/or TRAIL-R2 by inducing the formation of the so-called multiprotein death-inducing signaling complex (DISC)