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Updated: May 31, 2026
11:29
Isolation of Soluble and Insoluble PrP Oligomers in the Normal Human Brain
Published on: October 3, 2012
The pathological prion protein forms ionic conductance in lipid bilayer.
Daniele Paulis1, Bruno Maras, M Eugenia Schininà
1Dipartimento di Scienze Biomolecolari e Biotecnologie, University of Milan, Italy.
Neurochemistry International
|June 21, 2011
Summary
Transmissible spongiform encephalopathies (TSEs) involve prion protein (PrP(TSE)) altering membrane permeability. This study shows PrP27-30 forms pores in synthetic membranes, affecting conductance, while PrP90-231 interaction is amplified by calcium ions.
Area of Science:
- Neuroscience
- Biochemistry
- Membrane Biophysics
Background:
- Transmissible spongiform encephalopathies (TSEs) are fatal neurodegenerative diseases.
- Prion protein (PrP(TSE)) accumulation is a hallmark of TSEs.
- PrP(TSE) may induce neurodegeneration by altering cell membrane permeability.
Purpose of the Study:
- To investigate the in vitro effects of specific prion protein fragments on synthetic membrane permeability.
- To model the interaction of pathogenic prion protein isoforms with lipid bilayers.
Main Methods:
- Utilized synthetic lipid bilayers to model cellular membranes.
- Exposed membranes to PrP27-30 (extracted from infected brains) and PrP90-231 (recombinant peptide).
- Measured changes in membrane conductance and current amplitude under varying calcium ion concentrations.
Main Results:
- PrP27-30 induced the formation of molecular pores in synthetic membranes, significantly altering conductance.
- PrP90-231 showed a much lower conductance effect on synthetic membranes compared to PrP27-30.
- Increased calcium ion concentration amplified the interaction of PrP90-231 with the lipid bilayer and increased current amplitude for both peptides.
Conclusions:
- Pathological prion protein fragments can directly alter membrane properties by forming pores.
- The specific isoform and calcium concentration influence the interaction of prion proteins with lipid bilayers.
- These findings provide insights into the mechanisms of prion-induced neurotoxicity at the membrane level.
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