amyloid beta precursor protein binding family A member 2(APBA2) Homo sapiens The protein encoded by this gene is a member of the X11 protein family. It is a neuronal adapter protein that interacts with the Alzheimer’s disease amyloid precursor protein (APP). It stabilizes APP and inhibits production of proteolytic APP fragments including the A beta peptide that is deposited in the brains of Alzheimer’s disease patients. This gene product is believed to be involved in signal transduction processes. It is also regarded as a putative vesicular trafficking protein in the brain that can form a complex with the potential to couple synaptic vesicle exocytosis to neuronal cell adhesion. Multiple transcript variants encoding different isoforms have been found for this gene. [provided by RefSeq, Jul 2008],domain:Composed of an N-terminal domain that binds STXBP1, a middle phosphotyrosine-binding domain (PID/PTB) that mediates binding with the cytoplasmic domain of the beta-amyloid precursor protein, and two C-terminal PDZ domains thought to attach proteins to the plasma membrane.,function:Putative function in synaptic vesicle exocytosis by binding to STXBP1, an essential component of the synaptic vesicle exocytotic machinery. May modulate processing of the beta-amyloid precursor protein (APP) and hence formation of beta-APP.,similarity:Contains 1 PID domain.,similarity:Contains 2 PDZ (DHR) domains.,subunit:Part of a multimeric complex containing STXBP1 and syntaxin-1. Binds to the cytoplasmic domain of amyloid protein beta, and to the nuclear factor NF-kappa-B/p65 via its PDZ domain. Interacts with the amino-terminal domain of APBA2BP.,tissue specificity:Brain.,