Bcl XL Human, GST

B-Cell Lymphoma Extra Large (Bcl-xL) is a member of the Bcl-2 family of proteins, which are key regulators of apoptosis, the process of programmed cell death. Bcl-xL is an anti-apoptotic protein that plays a crucial role in cell survival by preventing the release of mitochondrial contents such as cytochrome c, which leads to caspase activation and ultimately, apoptosis .

Bcl-xL is encoded by the BCL2-like 1 gene and is a transmembrane molecule located in the mitochondria . The human recombinant form of Bcl-xL, expressed as a GST-tagged fusion protein, is produced in Escherichia coli (E. coli) and purified using proprietary chromatographic techniques . The recombinant protein is a single, non-glycosylated polypeptide chain containing 210 amino acids .

Bcl-xL is a multifunctional protein that not only inhibits apoptosis but also regulates other important cellular functions. It is overexpressed in many cancers, contributing to the survival of cancer cells by inhibiting the function of p53, a tumor suppressor . Bcl-xL also plays a role in the survival of erythroid progenitors, ensuring the production of red blood cells .

The primary function of Bcl-xL is to prevent apoptosis by inhibiting the release of cytochrome c from the mitochondria . This is achieved by binding to pro-apoptotic proteins such as Bax and Bak, preventing them from forming pores in the mitochondrial membrane . Additionally, Bcl-xL can bind directly to cytochrome c residues, further preventing apoptosis .

Bcl-xL is implicated in the survival of cancer cells and is a target for various senolytic agents, which are drugs that selectively induce death in senescent cells . Dysfunction of Bcl-xL in mice can lead to severe anemia, hemolysis, and death due to ineffective production of red blood cells . In cancerous cells, Bcl-xL helps them survive, making it a potential target for cancer therapy .