XAF1
Description
The XAF1 (XIAP associated factor 1) is a protein-coding gene located on chromosome 17.
XIAP-associated factor 1 (XAF1) is a protein encoded by the XAF1 gene in humans. X-linked inhibitor of apoptosis (XIAP) is a potent member of the IAP family, which contains baculoviral IAP (BIR) repeats that bind and inhibit caspases. XIAP has 3 BIR domains and a C-terminal RING zinc finger with E3 ubiquitin ligase activity.
XAF1 functions as a negative regulator of IAP family members. It inhibits the anti-caspase activity of BIRC4 by inducing its cleavage and inactivation, independent of caspase activation. XAF1 mediates TNF-alpha-induced apoptosis and is involved in apoptosis in trophoblast cells. It may indirectly inhibit BIRC4 by activating the mitochondrial apoptosis pathway. After translocation to mitochondria, XAF1 promotes translocation of BAX to mitochondria and cytochrome c release. It also promotes the redistribution of BIRC4 from the cytoplasm to the nucleus, likely independent of BIRC4 inactivation. The BIRC4-XAF1 complex mediates downregulation of BIRC5/survivin, requiring the E3 ligase activity of BIRC4. XAF1 seems to play a role in cellular sensitivity to TRAIL-induced apoptosis. As a potential tumor suppressor, XAF1 may contribute to apoptosis resistance in cancer cells.
XAF1 is also known as BIRC4BP, HSXIAPAF1, XIAPAF1.
Associated Diseases
- cancer
- nonpapillary renal cell carcinoma
- sarcoidosis
- gastric adenocarcinoma and proximal polyposis of the stomach
- gastric cancer
- chronic intestinal pseudoobstruction
- familial visceral myopathy
- glioblastoma
