Diablo Homolog (DIABLO)

DIABLO encodes an inhibitor of apoptosis protein (IAP)-binding protein. The encoded mitochondrial protein enters the cytosol when cells undergo apoptosis, and it moderates the caspase inhibition of IAPs. Multiple polyadenylation sites have been found for this gene. Four alternatively spliced transcript variants have been described for this gene, with two of them encoding different isoforms and the other two probably not encoding a protein.

The predicted SMAC polypeptide contains 239 amino acids. Northern blot analysis detected a 1.5-kb SMAC transcript in all tissues tested, with highest expression in adult testis, high expression in heart, liver, kidney, spleen, prostate, and ovary, and low expression in brain, lung, thymus, and peripheral blood leukocytes.