Alternative titles; symbols
HGNC Approved Gene Symbol: API5
Cytogenetic location: 11p12 Genomic coordinates (GRCh38) : 11:43,311,996-43,344,529 (from NCBI)
By screening for cDNAs that permitted survival of mouse fibroblasts in serum-free medium, followed by rescreening the cDNA library, Tewari et al. (1997) isolated short and long variants of Api5, which they called Aac11. They cloned human AAC11 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.
Tewari et al. (1997) found that mouse fibroblasts stably transfected with cDNA encoding the short isoform of mouse Aac11 were viable in serum-free medium. The protection was abolished by mutation of leucines to arginines within the leucine zipper domain. The longer Aac11 isoform did not protect against apoptosis.
Hartz (2005) mapped the API5 gene to chromosome 11p12 based on an alignment of the API5 sequence (GenBank U83857) with the genomic sequence (build 35).
Hartz, P. A. Personal Communication. Baltimore, Md. 12/12/2005.
Tewari, M., Yu, M., Ross, B., Dean, C., Giordano, A., Rubin, R. AAC-11, a novel cDNA that inhibits apoptosis after growth factor withdrawal. Cancer Res. 57: 4063-4069, 1997. [PubMed: 9307294]