Bcl2 Like Protein 13 (BCL2L13)

Bcl-rambo, a novel Bcl-2 homologue that induces apoptosis via its unique C-terminal extension. Bcl-rambo shows overall structural homology to the anti-apoptotic Bcl-2 members containing conserved Bcl-2 homology (BH) motifs 1, 2, 3, and 4. Unlike Bcl-2, however, the C-terminal membrane anchor region is preceded by a unique 250 amino acid insertion containing two tandem repeats. In mammalian cells, Bcl-rambo was localized to mitochondria, and its overexpression induces apoptosis that is specifically blocked by the caspase inhibitors, Surprisingly, the Bcl-rambo cell death activity was induced by its membrane-anchored C-terminal domain and not by the Bcl-2 homology region. Thus, Bcl-rambo constitutes a novel type of pro-apoptotic Bcl-2 member that triggers cell death independently of its BH motifs.