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Updated: Jun 13, 2026
11:29
Isolation of Soluble and Insoluble PrP Oligomers in the Normal Human Brain
Published on: October 3, 2012
Phospholipid composition of membranes directs prions down alternative aggregation pathways
Philip J Robinson1, Teresa J T Pinheiro
1Department of Biological Sciences, University of Warwick, Coventry, United Kingdom.
Biophysical Journal
|April 23, 2010
Summary
Prion protein (PrP) aggregation on membranes depends on lipid composition. Anionic lipids like POPS promote larger, disruptive aggregates, while zwitterionic lipids like POPC form uniform, non-disruptive structures.
Area of Science:
- Neuroscience
- Biochemistry
- Materials Science
Background:
- Prion diseases stem from misfolded prion protein (PrP).
- The hydrophobic membrane environment may influence PrP misfolding and aggregation.
- Understanding PrP-membrane interactions is crucial for prion disease research.
Purpose of the Study:
- To investigate how lipid composition affects prion aggregate morphology and growth mechanisms on membranes.
- To elucidate the role of zwitterionic and anionic lipids in PrP aggregation.
Main Methods:
- Atomic Force Microscopy (AFM) to image prion aggregation on supported lipid bilayers.
- Circular Dichroism (CD) spectroscopy to analyze PrP structural changes upon membrane interaction.
- Utilized lipid bilayers composed of POPC (zwitterionic) and POPS (anionic) mixtures.
Main Results:
- PrP interaction with POPS membranes increased beta-sheet structure, indicating altered conformation.
- PrP aggregation occurred on both POPC and POPS membranes.
- Aggregate morphology varied with anionic lipid content: POPC yielded uniform, non-disruptive aggregates; POPS resulted in larger, sponge-like, membrane-disruptive aggregates.
Conclusions:
- Lipid composition significantly influences prion protein aggregation morphology and growth on membranes.
- Anionic lipids promote distinct, disruptive aggregation pathways compared to zwitterionic lipids.
- PrP aggregation on membranes can be modeled using established growth principles.
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