This gene encodes an apoptosis inhibitory protein whose expression prevents apoptosis after growth factor deprivation. This protein suppresses the transcription factor E2F1-induced apoptosis and also interacts with, and negatively regulates Acinus, a nuclear factor involved in apoptotic DNA fragmentation. Its depletion enhances the cytotoxic action of the chemotherapeutic drugs. Multiple alternatively spliced transcript variants encoding different isoforms have been identified. [provided by RefSeq, Aug 2011],alternative products:Additional isoforms seem to exist,domain:Two regions, an N-terminal (aa 96-107) and a C-terminal (aa 274-311) are required for binding FGF2.,function:Antiapoptotic factor that may have a role in protein assembly. Negatively regulates ACIN1. By binding to ACIN1, it suppresses ACIN1 cleavage from CASP3 and ACIN1-mediated DNA fragmentation. Also known to efficiently suppress E2F1-induced apoptosis. Its depletion enhances the cytotoxic action of the chemotherapeutic drugs.,sequence caution:Translation N-terminally shortened.,similarity:Belongs to the API5 family.,subcellular location:Mainly nuclear. Can also be cytoplasmic.,subunit:Homooligomer. Interacts with FGF2 and ACIN1.,tissue specificity:Expressed in all tissues tested, including heart, brain, placenta, lung, liver, skeletal muscle, kidney and pancreas. Highest levels in heart, pancreas and placenta. Highly expressed in several cancers. Preferentially expressed in squamous cell carcinoma versus adenocarcinoma in non-small cell lung cancer.,
