One of the most intriguing disease-related mutations in human prion protein (PrP) is the Tyr to Stop codon substitution at position 145. This mutation results in a Gerstmann-Straussler-Scheinker-like disease with extensive PrP amyloid deposits in the brain. Here, we provide evidence for a spontaneous conversion of the recombinant polypeptide corresponding to the Y145Stop variant (huPrP23-144) from a monomeric unordered state to a fibrillar form. This conversion is characterized by a protein concentration-dependent lag phase and has characteristics of a nucleation-dependent polymerization. Atomic force microscopy shows that huPrP23-144 fibrils are characterized by an apparent periodicity along the long axis, with an average period of 20 nm. Fourier-transform infrared spectra indicate that the conversion is associated with formation of beta-sheet structure. However, the infrared bands for huPrP23-144 are quite different from those for a synthetic peptide PrP106-126, suggesting conformational non-equivalence of beta-structures in the disease-associated Y145Stop variant and a frequently used short model peptide. To identify the region that is critical for the self-seeded assembly of huPrP23-144 amyloid, experiments were performed by using the recombinant polypeptides corresponding to prion protein fragments 23-114, 23-124, 23-134, 23-137, 23-139, and 23-141. Importantly, none of the fragments ending before residue 139 showed a propensity for conformational conversion to amyloid fibrils, indicating that residues within the 138-141 region are essential for this conversion.
Download full-text PDF |
Source |
|---|---|
| http://www.ncbi.nlm.nih.gov/pmc/articles/PMC218714 | PMC |
| http://dx.doi.org/10.1073/pnas.2033281100 | DOI Listing |
Publication Analysis
Top Keywords
Similar Publications
Biomolecular condensates formed via phase separation of proteins and nucleic acids are crucial for the spatiotemporal regulation of a diverse array of essential cellular functions and the maintenance of cellular homeostasis. However, aberrant liquid-to-solid phase transitions of such condensates are associated with several fatal human diseases. Such dynamic membraneless compartments can contain a range of molecular chaperones that can regulate the phase behavior of proteins involved in the formation of these biological condensates.
View Article and Find Full Text PDFCopper binding alters the core structure of amyloid fibrils formed by Y145Stop human prion protein.
Phys Chem Chem Phys
October 2024
Department of Chemistry and Biochemistry, The Ohio State University, Columbus, OH, USA.
Transmissible spongiform encephalopathies (or prion diseases) such as Creutzfeldt-Jacob disease, mad cow disease, and scrapie are characterized by accumulation in the brain of misfolded prion protein aggregates (PrP) that have properties of amyloid fibrils. Given that transition metal ions, such as copper and zinc, appear to be important for physiological functions of cellular PrP (PrP) as well as for prion disease pathogenesis, exploring their role in the protein aggregation process is of considerable interest. Copper(II) in particular is well-known to bind to the four tandem octapeptide repeats (PHGGGWGQ) located in the N-terminal region of PrP (human PrP amino acids 60-91), as well as to additional histidine binding sites outside the octarepeat region with distinct binding modes depending on Cu concentration.
View Article and Find Full Text PDFInfluence of the Dynamically Disordered N-Terminal Tail Domain on the Amyloid Core Structure of Human Y145Stop Prion Protein Fibrils.
Front Mol Biosci
February 2022
Department of Chemistry and Biochemistry, The Ohio State University, Columbus, OH, United States.
The Y145Stop mutant of human prion protein (huPrP23-144) is associated with a familial prionopathy and provides a convenient model for investigating amyloid strains and cross-seeding barriers. huPrP23-144 fibrils feature a compact and relatively rigid parallel in-register -sheet amyloid core spanning ∼30 C-terminal amino acid residues (∼112-141) and a large ∼90-residue dynamically disordered N-terminal tail domain. Here, we systematically evaluate the influence of this dynamic domain on the structure adopted by the huPrP23-144 amyloid core region, by investigating using magic-angle spinning solid-state nuclear magnetic resonance (NMR) spectroscopy a series of fibril samples formed by huPrP23-144 variants corresponding to deletions of large segments of the N-terminal tail.
View Article and Find Full Text PDFAn intrinsically disordered pathological prion variant Y145Stop converts into self-seeding amyloids via liquid-liquid phase separation.
Proc Natl Acad Sci U S A
November 2021
Centre for Protein Science, Design and Engineering, Indian Institute of Science Education and Research Mohali, Punjab 140306, India;
Biomolecular condensation via liquid-liquid phase separation of intrinsically disordered proteins/regions (IDPs/IDRs) along with other biomolecules is proposed to control critical cellular functions, whereas aberrant phase transitions are associated with a range of neurodegenerative diseases. Here, we show that a disease-associated stop codon mutation of the prion protein (PrP) at tyrosine 145 (Y145Stop), resulting in a truncated, highly disordered, N-terminal IDR, spontaneously phase-separates into dynamic liquid-like droplets. Phase separation of this highly positively charged N-terminal segment is promoted by the electrostatic screening and a multitude of weak, transient, multivalent, intermolecular interactions.
View Article and Find Full Text PDFC and N chemical shift assignments of A117V and M129V human Y145Stop prion protein amyloid fibrils.
Biomol NMR Assign
April 2021
Department of Chemistry and Biochemistry, The Ohio State University, Columbus, OH, 43210, USA.
The C-terminally truncated Y145Stop variant of prion protein (PrP23-144) has been linked to a heritable prionopathy in humans and is also capable of triggering a transmissible prion disease in mice. PrP23-144 can be converted from soluble monomeric form to amyloid under physiological conditions, providing an in vitro model for investigating the molecular basis of amyloid strains and cross-seeding barriers. Here, we use magic-angle spinning solid-state NMR to establish the sequential backbone and sidechain C and N chemical shift assignments for amyloid fibrils formed by the A117V and M129V mutants of human PrP23-144, which in the context of full length PrP in vivo are among the specific residues associated with development of Gerstmann-Straüssler-Scheinker disease.
View Article and Find Full Text PDFWant AI Summaries of new PubMed Abstracts delivered to your In-box?
Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!