Alzheimer’s Disease  (AD) is a neurodegenerative disorder that is characterized by an abundance of  the beta-amyloid peptide in the brain.   When AD was first discovered, it was determined that beta-amyloid was  produced as a result of the proteolysis of the amyloid precursor protein  (APP).  Aside from its role in AD, the  single-pass transmembrane APP has a high expression level in the brain and  tends to concentrate at the synapses of neurons.  Because of this localization, it has been  suggested that APP plays a role in synapse formation and potentially  plasticity.  However, the