BAP31 monoclonal antibody (A1/182)

BAP31 (B cell receptor-associated protein 31) is an integral protein of the ER membrane that forms a large hetero-oligomeric complex with the related BAP29. The cytosolic domain of BAP31 contains two identical caspase recognition sites that are preferentially cleaved by initiator caspases, including caspase-8. After activation of cell surface death receptors, human BAP31 is cleaved into a membrane-embedded fragment called p20, which induces apoptosis when expressed ectopically. The p20 fragment can mediate Ca²⁺-dependent apoptotic cross-talk between the ER and mitochondria, stimulating cytochrome c release. In addition to its role in apoptosis, BAP31 is a component of the ER quality control compartment and functions as a cargo receptor for ER export of transmembrane proteins such as cellubrevin, MHC class I molecules, and cytochrome P450 2C2.