Role of lipid rafts and GM1 in the segregation and processing of prion protein.

The prion protein (PrPC) is highly expressed within the nervous system. Similar to other GPI-anchored proteins, PrPC is found in lipid rafts, membrane domains enriched in cholesterol and sphingolipids. PrPC raft association, together with raft lipid composition, appears essential for the conversion of PrPC into the scrapie isoform PrPSc, and the development of prion disease.

Characterization of prion protein-enriched domains, isolated from rat cerebellar granule cells in culture.

The biological functions of prion protein (PrP(C)) and its possible interaction with other specific molecular membrane partners remain largely unknown. The aim of this study is to gain information on the molecular environment of PrP(C) by analyzing the lipid and protein composition of a PrP(C)-enriched membrane subfraction, called prion domain, PrD. This domain was obtained by immunoprecipitation of detergent-resistant microdomains (DRM) of rat cerebellar granule cells under conditions designed to preserve lipid-mediated membrane organization.