Anti-Livin BIRC7 Antibody

Apoptosis, or programmed cell death, is related to many diseases, such as cancer. Apoptosis is triggered by a variety of stimuli including members in the TNF family and prevented by the inhibitor of apoptosis (IAP) proteins. IAP proteins form a conserved gene family that binds to and inhibits cell death proteases. A novel member in the IAP protein family was recently identified and designated Livin and KIAP for kidney IAP. Livin/XIAP contains a single baculoviral IAP repeat (BIR) domain and a RING finger domain and has two isoforms termed Livin-alpha and Livin-beta. Transfection of Livin in cells resulted in protection from apoptosis induced by FADD, BAX, RIP, RIP3 and DR6. Livin has direct interaction with several caspases including caspase-3, -7, and -9. Livin inhibits the activation of caspase-9 induced by Apaf-1, cytochrome c, and dATP. The two isoforms of Livin appear to have different functions and tissue distributions.

Livin antibody was raised against a 17 amino acid peptide near the carboxy terminus of human Livin. The immunogen is located within the last 50 amino acids of Livin.

Isoform 1 and isoform 2 are expressed at very low levels or not detectable in most adult tissues. Detected in adult heart, placenta, lung, lymph node, spleen and ovary, and in several carcinoma cell lines. Isoform 2 is detected in fetal kidney, heart and spleen, and at lower levels in adult brain, skeletal muscle and peripheral blood leukocytes.

Apoptotic regulator capable of exerting proapoptotic and anti-apoptotic activities and plays crucial roles in apoptosis, cell proliferation, and cell cycle control. Its anti-apoptotic activity is mediated through the inhibition of CASP3, CASP7 and CASP9, as well as by its E3 ubiquitin-protein ligase activity. As it is a weak caspase inhibitor, its anti-apoptotic activity is thought to be due to its ability to ubiquitinate DIABLO/SMAC targeting it for degradation thereby promoting cell survival. May contribute to caspase inhibition, by blocking the ability of DIABLO/SMAC to disrupt XIAP/BIRC4-caspase interactions. Protects against apoptosis induced by TNF or by chemical agents such as adriamycin, etoposide or staurosporine. Suppression of apoptosis is mediated by activation of MAPK8/JNK1, and possibly also of MAPK9/JNK2. This activation depends on TAB1 and NR2C2/TAK1. In vitro, inhibits CASP3 and proteolytic activation of pro-CASP9. Isoform 1 blocks staurosporine-induced apoptosis. Isoform 2 blocks etoposide-induced apoptosis. Isoform 2 protects against natural killer (NK) cell killing whereas isoform 1 augments killing.