XIAP Protein, Human (Avi)

XIAP protein is a multifunctional regulator that controls apoptosis, inflammation, immunity, copper homeostasis, and various signaling pathways. As a caspase inhibitor, it blocks CASP3 and CASP7 substrate access, keeping CASP9 inactive. XIAP Protein, Human (Avi) is the recombinant human-derived XIAP protein, expressed by E. coli , with C-Avi labeled tag. The total length of XIAP Protein, Human (Avi) is 236 a.a., with molecular weight of ~29.1 kDa.

The XIAP protein serves as a multifunctional regulator with diverse roles spanning apoptosis, inflammatory signaling, immunity, copper homeostasis, mitogenic kinase signaling, cell proliferation, invasion, and metastasis. As a direct caspase inhibitor, XIAP impedes substrate entry into the active site pockets of CASP3 and CASP7, while also maintaining CASP9 in a monomeric, inactive state. Functioning as an E3 ubiquitin-protein ligase, XIAP orchestrates ubiquitination of several target proteins, including RIPK1, RIPK2, MAP3K2/MEKK2, DIABLO/SMAC, AIFM1, CCS, PTEN, and BIRC5/survivin, thereby regulating NF-kappa-B signaling and other crucial pathways. In the realm of innate immunity, XIAP mediates 'Lys-63'-linked polyubiquitination of RIPK2 downstream of NOD1 and NOD2, activating NF-kappa-B and MAP kinases signaling. Additionally, XIAP influences the BMP signaling pathway, SMAD and MAP3K7/TAK1 dependent pathways, and the Wnt signaling cascade. It plays a role in copper homeostasis by ubiquitinating COMMD1 and also functions as an E3 ubiquitin-protein ligase in the NEDD8 conjugation pathway. Moreover, XIAP protects cells from spontaneous ripoptosome formation, suppresses ripoptosome formation by ubiquitinating RIPK1 and CASP8, and positively regulates Wnt signaling by ubiquitinating TLE proteins. These diverse functions underscore the intricate and pivotal role of XIAP in governing cellular processes across multiple signaling pathways.

Measured by its binding ability in a functional ELISA.Immobilized recombinant human SMAC-His at 10 μg/mL (100 μl/well) can bind recombinant human XIAP-AVI with a linear range of 0.125-1.0 μg/mL.

Human

E. coli

C-Avi

P98170 (L121-T356)

331  [NCBI]

Approximately 29.1 kDa

Greater than 95% as determined by reducing SDS-PAGE.

Lyophilized powder

Lyophilized from a 0.2 μm filtered solution of 25 mM Tris, 10 mM DTT, 1% Glycerol, 0.2 M Glutamine Potassium, pH 8.0. Normally 5 % - 8 % trehalose, mannitol and 0.01% Tween 80 are added as protectants before lyophilization.

It is not recommended to reconstitute to a concentration less than 100 μg/mL in ddH₂O.

Stored at -20°C for 2 years. After reconstitution, it is stable at 4°C for 1 week or -20°C for longer (with carrier protein). It is recommended to freeze aliquots at -20°C or -80°C for extended storage.

Room temperature in continental US; may vary elsewhere.