TRAIL peptide

Apoptosis or programmed cell death is induced in cells by a group of death domain containing receptors. Binding of ligand to these receptors sends signals that activate members of the caspase family of proteases. The signals ultimately cause degradation of chromosomal DNA by activating DNase. TRAIL (TNF related apoptosis induced ligand) or Apo 2L initiates apoptosis of tumor cells by binding to either of its receptors, DR4 or DR5. These receptors consist of an extracellular TRAIL binding domain and a cytoplasmic ""death domain"". In addition, two decoy receptors for TRAIL have also been identified. These receptors, designated DcR1 and DcR2, lack the death domain. Binding of TRAIL to either of these receptors, therefore, does not transmit the death signal. Thus, these receptors represent a novel way of regulating cell sensitivity to a pro-apoptotic cytokine at the cell surface. TRAIL is expressed predominantly in spleen, lung, and prostate but also in many other tissues.