DAP3 Antibody #2172

Death associated protein 1 (DAP1) is a 15 kDa protein that functions as a positive mediator of cell death initiated by interferon-gamma (1,2). The DAP1 protein is proline rich and possesses one SH3 binding motif, as well as several consensus protein kinase phosphorylation sites (1). The protein is localized in the cytoplasm, but the detailed mechanism of its proapoptotic function is unclear. Death associated protein 3 (DAP3) is widely expressed, and the expression is upregulated during membrane receptor-mediated apoptosis. In interferon-gamma- and Fas-induced apoptosis, DAP3 acts as a positive mediator, functioning downstream of the receptor signaling complex and upstream of the effector caspases (3,4). Death associated protein 5 (DAP5) is a 97 kDa protein with a high degree of amino acid sequence homology to eukaryotic translation initiation factor 4G (elF4G) (1,5). Compared with elF4G, DAP5 lacks the amino-terminal region necessary for cap-dependent translation, and has a unique carboxy-terminal region that functions as a regulator of interferon-gamma-induced cell death (5,6). During induction of apoptosis, DAP5 is cleaved at aspartic acid 790. The carboxy-terminal truncated form of DAP5 functions as a cap-independent translation initiation factor responsible for the mediation of its own translation during apoptosis (7).