Neurodevelopmental expression and localization of the cellular prion protein in the central nervous system of the mouse

Transmissible spongiform encephalopathies (TSEs) are neurodegenerative disorders caused by PrP Sc , or prion, an abnormally folded form of the cellular prion protein (PrP C ). The abundant expression of PrP C in the central nervous system (CNS) is a requirement for prion replication, yet despite years of intensive research the physiological function of PrP C still remains unclear. Several routes of investigation point out a potential role for PrP C in axon growth and neuronal development. Thus, we undertook a detailed analysis of the spatial and temporal expression of PrP C during mouse CNS development. Our findings show regional differences of the expression of PrP, with some specific white matter structures showing the earliest and highest expression of PrP C . Indeed, all these regions are part of the thalamolimbic neurocircuitry, suggesting a potential role of PrP C in the development and functioning of this specific brain system. J. Comp. Neurol. 518:1879–1891, 2010. © 2010 Wiley‐Liss, Inc.