Apoptosis Inhibitor 5 (API5)

AAC11 was cloned by database analysis and screening gingiva and leukemia cDNA libraries. The deduced 504-amino acid human protein shares a high degree of identity with the long mouse protein. AAC11 contains several protein phosphorylation sites, 2 N-glycosylation sites, and a leucine-rich sequence with weak similarity to a leucine zipper motif. Northern blot analysis detected a major Aac11 transcript in all adult and embryonic mouse tissues examined and several other transcripts expressed in a tissue-specific manner. AAC11 expression was also detected in several human tumor cell lines. Western blot analysis of mouse fibroblasts detected a major 55-kD protein and a minor 25-kD protein, corresponding to the long and short Aac11 isoforms, respectively.