Baculovirus inhibitors of apoptosis (IAPs) act in insect cells to prevent cell death.
NCBI Summary:
The protein encoded by this gene is a member of a family of proteins that inhibits apoptosis by binding to tumor necrosis factor receptor-associated factors TRAF1 and TRAF2, probably by interfering with activation of ICE-like proteases. The encoded protein inhibits apoptosis induced by serum deprivation but does not affect apoptosis resulting from exposure to menadione, a potent inducer of free radicals. The amino acid sequence predicts three baculovirus IAP repeat domains and a ring finger domain. Transcript variants encoding the same isoform have been identified.
General function
Cell death/survival, Anti-apoptotic
Comment
Cellular localization
Cytoplasmic
Comment
Ovarian function
Luteolysis
Comment
Lareu RR, et al 2003 reported regulated Expression of Inhibitor of Apoptosis Protein 3 in the Rat Corpus Luteum.
The authors sought to investigate the role inhibitor of apoptosis proteins (IAPs) play in the life cycle of the corpus luteum (CL) of the rat . They isolated two clones with amino acid homology to rat IAP2 (BIRC 3) and three to rat IAP3 (rIAP3; BIRC 4). The expression of rIAP3 mRNA was examined in the rat CL during and after pregnancy, in day 8 pregnant rats after 24 hour treatment of gonadotropin-releasing hormone-agonist (GnRH-Ag) and in a CL organ culture model of spontaneous apoptosis in the absence of tropic support with and without superoxide dismutase. Interestingly, a significant reduction in rIAP3 levels was seen at the time of CL regression in the course of natural pregnancy and the GnRH-Ag model. Surprisingly, rIAP3 mRNA levels in the CL organ culture model of spontaneous apoptosis failed to show significant changes although TUNEL (terminal deoxynucleotide transferase-mediated dUTP nick end-labelling) reaction showed 30-40% of the cells undergoing DNA fragmentation after 2 h in culture. In situ hybridization revealed that rIAP3 expression was localized to the cytoplasm of luteal and granulosa cells. These data clearly demonstrate both the presence of IAPs in the rat CL and the regulation of rIAP3 during in vivo apoptotic cell death, indicating a role for IAPs in the maintenance of CL function and demise.