Cellular Inhibitor of Apoptosis Protein 1

Cellular Inhibitor of Apoptosis Protein 1 (cIAP1), also known as BIRC2 (Baculoviral IAP Repeat Containing 2), is a protein that in humans is encoded by the BIRC2 gene. cIAP1 is a member of the Inhibitor of Apoptosis (IAP) family, which plays a critical role in regulating apoptosis and cell survival. This protein functions by inhibiting caspases, which are a family of protease enzymes playing essential roles in programmed cell death (apoptosis).

Function

cIAP1 is involved in the regulation of apoptosis and cell survival, acting primarily through its ability to inhibit caspases. It achieves this by directly binding to caspases through its Baculoviral IAP Repeat (BIR) domains, thereby preventing the caspases from initiating apoptosis. cIAP1 also participates in tumor necrosis factor (TNF) receptor signaling pathways, where it can promote cell survival by activating nuclear factor kappa B (NF-κB) and inhibiting the formation of a death-inducing signaling complex.

In addition to its role in apoptosis, cIAP1 is involved in various cellular processes, including cell proliferation, inflammation, and immune response. It has been shown to ubiquitinate certain substrates, leading to their degradation and thus modulating signaling pathways relevant to these processes.

Clinical Significance

Alterations in the expression or function of cIAP1 have been implicated in the development and progression of several types of cancer. Overexpression of cIAP1 has been observed in various cancers, where it contributes to tumor growth and survival by inhibiting apoptosis. This makes cIAP1 a potential target for cancer therapy, with several small molecule inhibitors being developed to specifically target and inhibit the function of IAP proteins, including cIAP1.

In addition to cancer, dysregulation of cIAP1 has been associated with other diseases, such as autoimmune disorders, making it a potential therapeutic target beyond oncology.

Genetics

The BIRC2 gene encoding cIAP1 is located on the short (p) arm of chromosome 11 at position 22. More specifically, it is situated at 11p22.2. This gene is part of a cluster of IAP genes located in this region of chromosome 11.

See Also

• Inhibitor of Apoptosis
• Caspase
• Tumor Necrosis Factor (TNF)
• Nuclear Factor Kappa B (NF-κB)
• Apoptosis