Recombinant Human BID Protein, CF

BID is a 195 amino acid member of the Bcl-2 family of proteins that regulates outer mitochondrial membrane permeability (1). BID is a pro-apoptotic member that causes cytochrome c to be released from the mitochondria intermembrane space into the cytosol. In healthy cells BID is cytosolic. In response to Fas ligand or TNF, BID is cleaved by caspase-8 and it then relocates to the mitochondria outer membrane (2, 3). Cleavage of BID by caspase-8 generates a new N-terminous that contains a terminal glycine. It appears that the glycine is myristoylated and myristoylation serves to target BID to the mitochondria (4). BID may then interact withanother pro-apoptotic Bcl-2 family member Bak (5). Interaction of BID with Bak causes altered mitochondrial membrane permeability. A (9-13) amino acid stretch called the BH3 region (Bcl-2 homology region) appears to mediate the BID interaction with other Bcl-2 family members. BID is neutralized by binding to the anti‑apoptotic member Bcl-xL.