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Updated: May 16, 2026
12:57
Investigating the Spreading and Toxicity of Prion-like Proteins Using the Metazoan Model Organism C. elegans
Published on: January 8, 2015
Cellular prion protein: from physiology to pathology.
Sei-ichi Yusa1, José B Oliveira-Martins, Yoshiko Sugita-Konishi
1Division of Microbiology, National Institute of Health Sciences, Tokyo, Japan. s-yusa@nihs.go.jp
Viruses
|December 4, 2012
Summary
Prion protein (PrP(C)) processing by proteases is crucial for normal function and preventing neurotoxicity. Understanding these proteases is key to prion disease research.
Area of Science:
- Neuroscience
- Biochemistry
- Molecular Biology
Background:
- The human cellular prion protein (PrP(C)) is a membrane glycoprotein with known N-glycosylation sites.
- PrP(C) processing yields N-terminal (N1) and C-terminal (C1) fragments, similar to amyloid precursor protein (APP) in Alzheimer's disease.
- The proteases responsible for PrP(C) cleavage and their roles in prion biology are not fully understood.
Purpose of the Study:
- To review historical and recent evidence on the proteases involved in cellular prion protein (PrP(C)) proteolysis.
- To elucidate the physiological and pathological significance of PrP(C) processing.
- To highlight recent advancements in understanding PrP(C) proteolysis in prion diseases.
Main Methods:
- Western blot analysis of human brain homogenates.
- PNGase F treatment to remove N-glycosylations and reveal PrP(C) fragments (N1 and C1).
- Review of experimental evidence and recent studies on PrP(C) proteolysis.
Main Results:
- PNGase F treatment unexpectedly generated two dominant PrP(C) fragments (N1 and C1).
- A strong correlation exists between neurotoxicity and impaired PrP(C) proteolysis.
- Non-cleavable PrP(C) mutants induce neurotoxicity, even without infectious prions.
Conclusions:
- PrP(C) proteolysis is physiologically and pathologically important.
- Understanding PrP(C) processing is critical for comprehending prion biology and disease mechanisms.
- Recent research and mouse models are advancing knowledge of PrP(C)-cleaving proteases.
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