Prion protein protects mice from lethal infection with influenza A viruses.

The cellular prion protein, designated PrPC, is a membrane glycoprotein expressed abundantly in brains and to a lesser extent in other tissues. Conformational conversion of PrPC into the amyloidogenic isoform is a key pathogenic event in prion diseases. However, the physiological functions of PrPC remain largely unknown, particularly in non-neuronal tissues.

Prion Protein Devoid of the Octapeptide Repeat Region Delays Bovine Spongiform Encephalopathy Pathogenesis in Mice.

Conformational conversion of the cellular isoform of prion protein, PrP, into the abnormally folded, amyloidogenic isoform, PrP, is a key pathogenic event in prion diseases, including Creutzfeldt-Jakob disease in humans and scrapie and bovine spongiform encephalopathy (BSE) in animals. We previously reported that the octapeptide repeat (OR) region could be dispensable for converting PrP into PrP after infection with RML prions. We demonstrated that mice transgenically expressing mouse PrP with deletion of the OR region on the PrP knockout background, designated Tg(PrPΔOR)/ mice, did not show reduced susceptibility to RML scrapie prions, with abundant accumulation of PrPΔOR in their brains.

Prions amplify through degradation of the VPS10P sorting receptor sortilin.

Prion diseases are a group of fatal neurodegenerative disorders caused by prions, which consist mainly of the abnormally folded isoform of prion protein, PrPSc. A pivotal pathogenic event in prion disease is progressive accumulation of prions, or PrPSc, in brains through constitutive conformational conversion of the cellular prion protein, PrPC, into PrPSc. However, the cellular mechanism by which PrPSc is progressively accumulated in prion-infected neurons remains unknown.

Effects of prion protein devoid of the N-terminal residues 25-50 on prion pathogenesis in mice.

The N-terminal polybasic region of the normal prion protein, PrP, which encompasses residues 23-31, is important for prion pathogenesis by affecting conversion of PrP into the pathogenic isoform, PrP. We previously reported transgenic mice expressing PrP with residues 25-50 deleted in the PrP-null background, designated as Tg(PrP∆preOR)/Prnp mice. Here, we produced two new lines of Tg(PrP∆preOR)/Prnp mice, each expressing the mutant protein, PrP∆preOR, 1.

Mouse-hamster chimeric prion protein (PrP) devoid of N-terminal residues 23-88 restores susceptibility to 22L prions, but not to RML prions in PrP-knockout mice.

Prion infection induces conformational conversion of the normal prion protein PrPC, into the pathogenic isoform PrPSc, in prion diseases. It has been shown that PrP-knockout (Prnp0/0) mice transgenically reconstituted with a mouse-hamster chimeric PrP lacking N-terminal residues 23-88, or Tg(MHM2Δ23-88)/Prnp 0/0 mice, neither developed the disease nor accumulated MHM2ScΔ23-88 in their brains after inoculation with RML prions. In contrast, RML-inoculated Tg(MHM2Δ23-88)/Prnp 0/+ mice developed the disease with abundant accumulation of MHM2ScΔ23-88 in their brains.