XIAP Associated Factor 1 (XAF1) Antibody – Rabbit Polyclonal

X-linked inhibitor of apoptosis (XIAP; MIM 300079) is a potent member of the IAP family. All members of this family possess baculoviral IAP (BIR) repeats, cysteine-rich domains of approximately 80 amino acids that bind and inhibit caspases (e.g., CASP3; MIM 600636). XIAP has 3 BIR domains and a C-terminal RING zinc finger that possesses E3 ubiquitin ligase (see MIM 601623) activity. XAF1 antagonizes the anticaspase activity of XIAP and may be important in mediating apoptosis resistance in cancer cells (Liston et al., 2001 [PubMed 11175744]).[supplied by OMIM]

BIRC4BP: Seems to function as a negative regulator of members of the IAP (inhibitor of apoptosis protein) family. Inhibits anti- caspase activity of BIRC4. Induces cleavage and inactivation of BIRC4 independent of caspase activation. Mediates TNF-alpha- induced apoptosis and is involved in apoptosis in trophoblast cells. May inhibit BIRC4 indirectly by activating the mitochondrial apoptosis pathway. After translocation to mitochondra, promotes translocation of BAX to mitochondria and cytochrome c release from mitochondria. Seems to promote the redistribution of BIRC4 from the cytoplasm to the nucleus, probably independent of BIRC4 inactivation which seems to occur in the cytoplasm. The BIRC4-XAF1 complex mediates down-regulation of BIRC5/survivin; the process requires the E3 ligase activity of BIRC4. Seems to be involved in cellular sensitivity to the proapoptotic actions of TRAIL. May be a tumor suppressor by mediating apoptosis resistance of cancer cells. 7 isoforms of the human protein are produced by alternative splicing.

Protein type: Apoptosis; Tumor suppressor

Chromosomal Location of Human Ortholog: 17p13.1

Cellular Component: mitochondrion; cytosol; nucleus

Molecular Function: zinc ion binding

Biological Process: apoptosis; cytokine and chemokine mediated signaling pathway; negative regulation of protein complex assembly