Related Experiment Video
Updated: Jun 9, 2026
Protein Misfolding Cyclic Amplification of Prions
Published on: November 7, 2012
Prion strain interactions are highly selective
K Peter R Nilsson1, Shivanjali Joshi-Barr, Olivia Winson
1Department of Physics, Chemistry, and Biology, Linköping University, Linköping, Sweden.
Abstract:
Various misfolded and aggregated neuronal proteins commonly coexist in neurodegenerative disease, but whether the proteins coaggregate and alter the disease pathogenesis is unclear. Here, we used mixtures of distinct prion strains, which are believed to differ in conformation, to test the hypothesis that two different aggregates interact and change the disease in vivo. We tracked two prion strains in mice histopathologically and biochemically, as well as by spectral analysis of plaque-bound PTAA (polythiophene acetic acid), a conformation-sensitive fluorescent amyloid ligand. We found that prion strains interacted in a highly selective and strain-specific manner, with (1) no interaction, (2) hybrid plaque formation, or (3) blockage of one strain by a second (interference). The hybrid plaques were maintained on additional passage in vivo and each strain seemed to maintain its original conformational properties, suggesting that one strain served only as a scaffold for aggregation of the second strain. These findings not only further our understanding of prion strain interactions but also directly demonstrate interactions that may occur in other protein aggregate mixtures.
Insights
Two different prion strains can interact in mice, forming hybrid plaques or interfering with each other. These prion protein interactions reveal insights into neurodegenerative disease mechanisms.
Area of Science:
- Neuroscience
- Biochemistry
- Protein Misfolding Diseases
Background:
- Misfolded and aggregated neuronal proteins often coexist in neurodegenerative diseases.
- The interactions and coaggregation of these proteins and their impact on disease pathogenesis remain largely unclear.
Purpose of the Study:
- To investigate whether distinct prion strains, differing in conformation, interact and alter disease progression in vivo.
- To test the hypothesis of cross-seeding and interference between different prion protein aggregates.
Main Methods:
- Tracking two distinct prion strains in mice using histopathology and biochemical analysis.
- Utilizing spectral analysis of plaque-bound polythiophene acetic acid (PTAA), a conformation-sensitive fluorescent amyloid ligand.
Main Results:
- Demonstrated highly selective and strain-specific interactions between prion strains.
- Observed three interaction outcomes: no interaction, hybrid plaque formation, or interference (blockage).
- Hybrid plaques were stable upon further passage, with strains retaining original conformational properties, suggesting a scaffold-like role.
Conclusions:
- Prion strain interactions are specific and can lead to novel aggregate structures or interference.
- Findings provide direct evidence for interactions between different protein aggregates, relevant to various neurodegenerative diseases.
- This study advances the understanding of prion biology and protein aggregation in disease contexts.
Related Concept Videos
02:04Protein-protein Interfaces
00:57Antibiotic Selection
03:03Amyloid Fibrils
Amyloid deposits were observed as early as 1639 in the liver and the spleen. In 1854, Rudolph Virchow performed iodine staining, normally used to...
01:57Protein Complexes with Interchangeable Parts
The SCF ubiquitin ligase is a protein complex of five individual proteins. This complex attaches ubiquitin to other target proteins to mark them for degradation. In order to...