PrPSc in N2a-FK cells is markedly degraded by the autophagy pathway.

Persistently prion-infected cells were treated with 1 to 10 mM of 3-methyladenine (3MA) and 0.2 to 1 μM rapamycin (Rap) for 48 h. Proteinase K (PK)-treated N2a-FK, -22L and-Ch cells, which vary in the prion strains, were loaded at concentrations of 100, 60 and 35 μg protein per lane onto a 15% polyacrylamide gels and subjected to SDS-PAGE. PrPSc was detected by western blotting using an anti-PrP antibody. For densitometric analysis, the images were scanned and the intensity of each band on the western blotting was quantified with respect to PrPSc expression levels in drug-treated prion-infected cells, respectively. The results are representative of at least three independent experiments, with each experiment performed in triplicate. *p < 0.05 and **p < 0.01 (one-way ANOVA followed by Tukey's test).