Trafficking of the cellular isoform of the prion protein

Transmissible spongiform encephalopathies form a group of fatal neurodegene rative disorders that have the unique property of being infectious, sporadi c or genetic in origin. Although the nature of the responsible agent of the se diseases is uncertain, it is clear that a protein called PrPSc has a cen tral role in their pathology. PrPSc is a conformational variant of a normal protein called PrPC. Understanding the transition from PrPC to PrPSc is a major issue in the field. In this article, we will review what is known abo ut the cell biology of PrPC, the understanding of which is crucial consider ing that trafficking of this molecule governs generation of PrPSc. (C) 1999 Elsevier, Paris.