Liquid-liquid Phase Separation and Fibrillation of the Prion Protein Modulated by a High-affinity DNA Aptamer

Authors

Carolina O. Matos, Institute of Chemistry, Federal University of Rio de Janeiro
Yulli M. Passos, Federal University of Rio de Janeiro
Mariana J. Amaral, Institute of Medical Biochemistry Leopoldo de Meis
Bruno Macedo, Federal University of Rio de Janeiro
Matheus H. Tempone, Federal University of Rio de Janeiro
Ohanna C. Bezerra, Oswaldo Cruz Institute
Milton O. Moraes, Oswaldo Cruz Institute
Marcius S. Almeida, Institute of Chemistry, Federal University of Rio de Janeiro
Gerald Weber, Federal University of Minas Gerais
Sotiris Missailidis, Institute of Technology in Immunobiologics (Bio-Manguinhos)
Jerson L. Silva, Institute of Medical Biochemistry Leopoldo de Meis
Vladimir N. Uversky, University of South FloridaFollow
Anderson S. Pinheiro, Institute of Chemistry, Federal University of Rio de Janeiro
Yraima Cordeiro, Federal University of Rio de Janeiro

Document Type

Article

Publication Date

2020

Keywords

neurodegenerative diseases, nucleic acid, phase transitions, prions, SELEX

Digital Object Identifier (DOI)

https://doi.org/10.1096/fj.201901897R

Abstract

Structural conversion of cellular prion protein (PrPC) into scrapie PrP (PrPSc) and subsequent aggregation are key events associated with the onset of transmissible spongiform encephalopathies (TSEs). Experimental evidence supports the role of nucleic acids (NAs) in assisting this conversion. Here, we asked whether PrP undergoes liquid-liquid phase separation (LLPS) and if this process is modulated by NAs. To this end, two 25-mer DNA aptamers, A1 and A2, were selected against the globular domain of recombinant murine PrP (rPrP90-231) using SELEX methodology. Multiparametric structural analysis of these aptamers revealed that A1 adopts a hairpin conformation. Aptamer binding caused partial unfolding of rPrP90-231 and modulated its ability to undergo LLPS and fibrillate. In fact, although free rPrP90-231 phase separated into large droplets, aptamer binding increased the number of droplets but noticeably reduced their size. Strikingly, a modified A1 aptamer that does not adopt a hairpin structure induced formation of amyloid fibrils on the surface of the droplets. We show here that PrP undergoes LLPS, and that the PrP interaction with NAs modulates phase separation and promotes PrP fibrillation in a NA structure and concentration-dependent manner. These results shed new light on the roles of NAs in PrP misfolding and TSEs.

Was this content written or created while at USF?

Yes

Citation / Publisher Attribution

The FASEB Journal, v. 34, issue 1, p. 365-385

Scholar Commons Citation

Matos, Carolina O.; Passos, Yulli M.; Amaral, Mariana J.; Macedo, Bruno; Tempone, Matheus H.; Bezerra, Ohanna C.; Moraes, Milton O.; Almeida, Marcius S.; Weber, Gerald; Missailidis, Sotiris; Silva, Jerson L.; Uversky, Vladimir N.; Pinheiro, Anderson S.; and Cordeiro, Yraima, "Liquid-liquid Phase Separation and Fibrillation of the Prion Protein Modulated by a High-affinity DNA Aptamer" (2020). Molecular Medicine Faculty Publications. 155.
https://digitalcommons.usf.edu/mme_facpub/155