Protein Phosphorylation Regulates the Cellular Trafficking and Processing of the Alzheimer Beta/A4 Amyloid Precursor Protein
Cerebral deposition of the beta/A4 amyloid peptide is an important feature of Alzheimer disease. The beta/A4 peptide is derived from the amyloid precursor protein (APP), a transmembrane glycoprotein whose function is unknown. Abnormal processing of APP has been causally linked to Alzheimer disease since mutations in the coding sequence of APP are associated with an inherited early-onset form of the disease. We have employed the rat neuroendocrine PC12 cell line to examine the normal cellular trafficking and proteolytic processing of APP and to investigate the role of protein phosphorylation in the regulation of normal and aberrant APP metabolism.