Peptide corresponding to amino acids 149 to 167 at extracellular domain (ED) of human DcR1 precursor (2-3). Apoptosis is induced by certain cytokines including TNF and Fas ligand in the TNF family through their death domain containing receptors. TRAIL/Apo2L is a new member of the TNF family and induces apoptosis of a variety of tumor cell lines. DR4 and DR5 are the recently identified functional receptors for TRAIL (1-3). Two decoy receptors for TRAIL have been identified and designated DcR1/TRID/TRAIL-R3/LIT (2-7) and DcR2/TRAIL-R4/ TRUNDD (8-10). DcR1 has extracellular TRAIL-binding domain but lacks intracellular signaling domain. It is a glycophospholipid-anchored cell surface protein. DcR1 transcripts were expressed in many normal human tissues. But not in most cancer cell lines (2,3) Overexpression of DcR1 did not induce apoptosis, but attenuated TRAIL-induced apoptosis (2,3).
