| abstract |
The present invention provides a Bcl-2-interacting protein. This Bcl-2-interacting protein has been purified and shown to be identical to a previously described 28 kDa protein (p28) called Bap31 /CDM. Human p28 is a polytopic integral protein of the endoplasmic reticulum (ER) whose cytosolic domain contains overlapping death effector domain and leucine zipper homologies, flanked on either side by identical caspase recognition sites. Following apoptotic stimuli in the absence of Bcl-2, p28 was cleaved at both caspase recognition sites. One of the cleavage products, p20, caused induction of apoptosis when expressed ectopically in otherwise normal cells. All of these events were prevented by elevated expression of Bcl-2. p28 Bap31 may be a Bcl-2-regulated component of an apoptosis signaling pathway, perhaps involving coordinated ER-mitochondrial events. P28 Bap31 itself or the cleavage of p28 Bap31 and the cleavage products thereof are useful in diagnostic kits, laboratory reagents, assays and development of reagents for the treatment of disease relating to apoptosis. |