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Prions and their partners in crime

Abstract

Prions, the infectious agents of transmissible spongiform encephalopathies (TSEs), have defied full characterization for decades. The dogma has been that prions lack nucleic acids and are composed of a pathological, self-inducing form of the host's prion protein (PrP). Recent progress in propagating TSE infectivity in cell-free systems has effectively ruled out the involvement of foreign nucleic acids. However, host-derived nucleic acids or other non-PrP molecules seem to be crucial. Interactions between TSE-associated PrP and its normal counterpart are also pathalogically important, so the physiological functions of normal PrP and how they might be corrupted by TSE infections have been the subject of recent research.

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Figure 1: Different patterns of PrPres deposition in brain tissue of mice expressing wild-type versus anchorless PrPC.
Figure 2: Model of potential PrPC interactions associated with axonal growth.

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Acknowledgements

We gratefully acknowledge the helpful comments of W. Caughey, U. Dittmer, B. Chesebro, S. Priola, V. Sim, D. Kocisko, K. Sun Lee and J. Silveira. This work was supported by the Intramural Program of NIAID, NIH.

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Caughey, B., Baron, G. Prions and their partners in crime. Nature 443, 803–810 (2006). https://doi.org/10.1038/nature05294

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