Alzheimer's disease is characterized pathologically by senile plaques in the brain. The major component of senile plaques is amyloid-beta (Abeta), which is cleaved from Alzheimer's Abeta protein precursor (AbetaPP). Recently, information regarding the cytoplasmic tail of AbetaPP has started to emerge, opening up various insights into the physiological roles of AbetaPP and its pathological role in Alzheimer's disease. The cytoplasmic domain of AbetaPP shares the evolutionarily conserved GYENPTY motif, which binds to a number of adaptor proteins containing the phosphotyrosine interaction domain (PID). Among the PID-containing proteins, this article focuses on four groups of adaptor proteins of AbetaPP: Fe65, X11, mDab1, and c-Jun N-terminal kinase-interacting protein 1b/islet-brain 1.