Apoptosis regulator Bcl-X (Bcl-X)

Bcl-X is a key regulator of apoptosis in mammalian cells and is a member of the Bcl-2 protein family. The protein exists in multiple isoforms due to alternative RNA splicing, with the most studied forms being Bcl-xL (long), which inhibits apoptosis, and Bcl-xS (short), which promotes apoptosis. Bcl-xL acts as an inhibitor of cell death by preventing the release of mitochondrial cytochrome c and inhibiting activation or membrane insertion of pro-apoptotic proteins Bax/Bak. Bcl-xS promotes cell death by binding/inhibiting antiapoptotic members like Bcl-xL/BCL2 via heterodimerization and releasing Bak from inhibition to trigger MOMP.

Other names

Bcl-xLBcl-xSBCL2L1

Inhibition of Bcl-xL, promotion of Bcl-xS