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Published on: July 16, 2008
Mechanisms of prion protein aggregation
Sarah N Fontaine1, David R Brown
1Department of Biology and Biochemistry, University of Bath, Claverton Down, Bath, BA2 7AY, UK.
Protein and Peptide Letters
|January 20, 2009
Summary
Prion diseases involve abnormal prion protein (PrP) aggregation. While fibrils are common, soluble oligomers are more infectious and neurotoxic, challenging the view of fibrils as the primary disease driver.
Area of Science:
- Neuroscience
- Biochemistry
- Molecular Biology
Background:
- The prion protein (PrP) exists as a normal, neuroprotective isoform and an abnormal, disease-associated isoform.
- Prion diseases are characterized by the conversion of normal PrP to a protease-resistant, toxic form.
Purpose of the Study:
- To review mechanisms of prion protein aggregation.
- To examine the relevance of different aggregated forms (oligomers, fibrils) in prion disease pathogenesis.
Main Methods:
- Literature review of recent studies on prion protein aggregation.
- Analysis of experimental data on prion infectivity and neurotoxicity.
Main Results:
- Abnormal PrP can aggregate into both soluble oligomers and insoluble fibrils.
- Oligomers, not fibrils, are the most infectious form of prions.
- Neurotoxicity is primarily linked to smaller aggregates, including oligomers.
Conclusions:
- Fibrils may represent an inert "bulk" form of abnormal PrP.
- Oligomeric aggregates are key players in prion infectivity and neurotoxicity.
- Understanding aggregation mechanisms is crucial for prion disease therapeutics.
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