Prion Protein (Ser-43), Phosphospecific Antibody

Prion related neurodegenerative diseases, called transmissible spongiform encephalopathies, are observed in many animal species. These diseases involve conversion of normal cellular prion protein (PrPc) into a form that is insoluble and resistant to proteases (PrPSc) . The protease resistant form can polymerize into fibrils which accumulate in infected tissues and cause cell death and tissue damage. PrPs have an N-terminal signal sequence and a C-terminal linkage to glycosylphosphatidylinositol anchor. The mature protein is a glycosylated protein that associates with cell membranes. Phosphorylation of PrPC at Ser-43 by Cdk5 promotes proteinase K resistance, prion aggregation, and fibril formation in vitro. In addition, Ser-43 phosphorylation is upregulated in scrapie-infected mouse brain relative to controls. Thus, phosphorylation of Ser-43 may be an important mechanism leading conversion of PrPc to PrPSc and the onset of disease.

The antibody detects a human recombinant Prion protein after phosphorylation by Cdk5/p25 complex. In addition, the antibody may detect aggregrated forms of prion in human PC3 cells treated with Calyculin A. This sequence has high homology to the conserved site in rat, mouse, and bovine prion protein.