Phosphatidic Acid Vesicles Convert the Prion Protein into β-Sheet Fibrils with a Thermostable Structure but Temperature-Sensitive Packing
4 affiliations
- 1Programa de Biologia Estrutural, Instituto de Bioquímica Médica Leopoldo de Meis, Instituto Nacional de Ciência e Tecnologia de Biologia Estrutural e Bioimagem (INBEB), Universidade Federal do Rio de Janeiro (UFRJ), Rio de Janeiro 21941-599, Brazil
- 2Physical Chemistry I—Biophysical Chemistry, Department of Chemistry and Chemical Biology, TU Dortmund University, 44227 Dortmund, Germany
- 3Instituto D’Or de Pesquisa e Ensino IDOR, Rio de Janeiro 22281-100, Brazil
- 4Faculdade de Medicina e Ciências Biomédicas, Algarve Biomedical Center Research Institute (ABC-Ri), Algarve Biomedical Center (ABC), University of Algarve, 8005-139 Faro, Portugal
Abstract
Biomolecular cofactors, including nucleic acids and lipids, promote conversion of the cellular prion protein (PrPC) into pathogenic assemblies (prion scrapie, PrPSc), yet the mechanistic role of specific membrane lipids in the earliest stages remains unclear. Previous work showed that phosphatidic acid (PA) vesicles interact in vitro with murine recombinant PrP (recPrP) and trigger PrP aggregation without additional cofactors. Here, we dissect the PA-driven conversion pathway by monitoring PrP assembly and aggregate stability using spectroscopy and by comparing full-length recPrP with an N-terminally truncated construct. PA vesicles induced aggregation in both PrP constructs with similar efficiency, indicating that PA-mediated conversion does not require residues 23–89. Thermal stability analyses revealed a thermally resilient β-structured state accompanied by temperature-sensitive, partially reversible ThT binding, which we interpret as remodelling of higher-order packing. Time-resolved measurements showed that assembly reached a plateau within the measurement time resolution at all temperatures tested, with no resolvable lag phase. At plateau, the extent of ThT-positive assembly was greatest under conditions of higher bilayer order, while light scattering and secondary-structure content were comparable across temperatures. PrP alone showed no detectable temperature-dependent secondary-structure changes between 10 and 40 °C, consistent with membrane organization contributing to assembly architecture. Together, these results establish PA vesicles as a tractable model for interrogating cofactor-driven early prion aggregation and support membrane lipids and their physical state as modulators of PrP conversion into β-structured assemblies, with implications for mechanistic studies and screening strategies targeting lipid–protein interactions.
Related
- Thermostable Carbohydrate-Active Enzymes for High-Temperature Biomass Conversion: From Molecular Design to Process Integration
- Actin filament bundling by the Arabidopsis VILLIN4 C-terminus involves the basic segment of the IDR linker and is sensitive to temperature and ionic strength
- SSAlign: fast and sensitive protein structure search at scale
- Quantitative Bioluminescent Imaging of AHR Activity Using a Thermostable Variant of the Fungal Luciferase nnLuz
- Characterisation of thermostable CYP116B reductase domains as modular electron transfer units for redox biocatalysis
BibTeX
@article{alves2026phosphatidic,
title = {{Phosphatidic Acid Vesicles Convert the Prion Protein into β-Sheet Fibrils with a Thermostable Structure but Temperature-Sensitive Packing}},
author = {Cyntia Alves and Gabriela Assis-de-Lemos and Michel W. Jaworek and Guilherme A. P. de Oliveira and Roland Winter and Jerson Lima Silva and Tuane C. R. G. Vieira},
journal = {International journal of molecular sciences},
year = {2026},
month = oct,
doi = {10.3390/ijms27198826},
url = {https://europepmc.org/article/PMC/PMC13665344},
note = {CC BY},
}
RIS
TY - JOUR
TI - Phosphatidic Acid Vesicles Convert the Prion Protein into β-Sheet Fibrils with a Thermostable Structure but Temperature-Sensitive Packing
AU - Cyntia Alves
AU - Gabriela Assis-de-Lemos
AU - Michel W. Jaworek
AU - Guilherme A. P. de Oliveira
AU - Roland Winter
AU - Jerson Lima Silva
AU - Tuane C. R. G. Vieira
PY - 2026
DA - 2026/10/01
JO - International journal of molecular sciences
DO - 10.3390/ijms27198826
UR - https://europepmc.org/article/PMC/PMC13665344
AB - Biomolecular cofactors, including nucleic acids and lipids, promote conversion of the cellular prion protein (PrPC) into pathogenic assemblies (prion scrapie, PrPSc), yet the mechanistic role of specific membrane lipids in the earliest stages remains unclear. Previous work showed that phosphatidic acid (PA) vesicles interact in vitro with murine recombinant PrP (recPrP) and trigger PrP aggregation without additional cofactors. Here, we dissect the PA-driven conversion pathway by monitoring PrP assembly and aggregate stability using spectroscopy and by comparing full-length recPrP with an N-terminally truncated construct. PA vesicles induced aggregation in both PrP constructs with similar efficiency, indicating that PA-mediated conversion does not require residues 23–89. Thermal stability analyses revealed a thermally resilient β-structured state accompanied by temperature-sensitive, partially reversible ThT binding, which we interpret as remodelling of higher-order packing. Time-resolved measurements showed that assembly reached a plateau within the measurement time resolution at all temperatures tested, with no resolvable lag phase. At plateau, the extent of ThT-positive assembly was greatest under conditions of higher bilayer order, while light scattering and secondary-structure content were comparable across temperatures. PrP alone showed no detectable temperature-dependent secondary-structure changes between 10 and 40 °C, consistent with membrane organization contributing to assembly architecture. Together, these results establish PA vesicles as a tractable model for interrogating cofactor-driven early prion aggregation and support membrane lipids and their physical state as modulators of PrP conversion into β-structured assemblies, with implications for mechanistic studies and screening strategies targeting lipid–protein interactions.
SN - 1422-0067
ER -