A plausible function of the prion protein: conjectures and a hypothesis

Amyloid beta precursor protein (APP) and prion protein (PrP) are cell membrane elements implicated in neurodegenerative diseases. Both proteins undergo endoproteolysis. Evidence is adduced from the literature hinting that the process in the two proteins could be related, their functions may overlap and their distributions coincide. It is proposed that PrP catalyses its own cleavage, the C-terminal fragment functions as an alpha secretase and the N-terminal segment chaperones the active site; the alpha secretase releases anticoagulant and neurotrophic ectodomains from APP. The proposals explain some features of spongiform encephalopathies, (C) 2001 John Wiley & Sons, Inc.