Heat shock modulates prion protein expression in human NT2 cells

The pathological hallmarks of Prion disease are cortical spongi-form changes and neuronal loss, which are induced by the accumulation of the scrapie-isoform prion protein (PrPSc). PrPScis derived from a post-translational modification of the cellular form of prion protein (PrPC). Heat-shock proteins, a group of molecular chaperones, are involved in the degradation of denatured proteins and post-translational folding of newly synthesized polypeptides. In an attempt to examine any possible relationship between heat shock stress and an induction of prion protein (PrP), human NT-2 cells were treated with heat shock at 42°C for 30 min. After heat-shock treatment, both the level of mRNA and PrPCprotein were analyzed at various time points by Northern and Western blot, respectively. There was a 1.5-to 2.5-fold increase in PrP mRNA levels 1 and 3 h following heat shock. In addition, a two-fold increase in protein level of PrP was found 3 h after heat-shock treatment. These results suggest that cellular stress induces the elevation of both PrP mRNA and protein synthesis. The up-regulation of prion-protein mRNA and protein, implies that PrP may play a role in cellular stress.