Prion Protein/CD230

Prion protein is the protein responsible for human Creutzfeldt-Jakob Disease (CJD), and somatic mutations of the prion gene are responsible for Gerstmann-Straussler-Scheinker disease and Fatal Familial Insomnia. The bovine homolog of the prion protein is responsible for bovine Spongioform Encephalopathy (BSE), also known as “Mad Cow Disease.” In all cases, the prion protein has two folding states, with one state being the “normal” non-pathological form, and the other state inducing a spongioform encephalopathy.

Normal prion proteins produced naturally in the brain interact with the amyloid-β peptides that are hallmarks of Alzheimer's disease. Blocking this interaction in preparations made from mouse brains halted some neurological defects caused by the accumulation of amyloid-β peptide. It was previously thought that only infectious prion proteins, rather than their normal, non-infectious counterparts, played a role in brain degeneration (Nature, doi:10.1038/news.2009.121).