PRNP and prion disease: While our study did not directly address the importance of cytosolic PrP species in prion diseases, lack of effects in our transgenic mice with high N1 (or better: N1-SP) levels in the cytoplasm (as demonstrated in N1-transfected cells) at least indicates that N1 does not confer protection against cytPrP-mediated toxicity or cytosolic prions.