UZH-Logo

Multiple substitutions of methionine 129 in human prion protein reveal its importance in the amyloid fibrillation pathway


Nystrom, Sofie; Mishra, Rajesh; Hornemann, Simone; Aguzzi, Adriano; Nilsson, K Peter R; Hammarstrom, Per (2012). Multiple substitutions of methionine 129 in human prion protein reveal its importance in the amyloid fibrillation pathway. Journal of Biological Chemistry, 287(31):25975-25984.

Abstract

The role of the polymorphism 129M/V in the human prion protein is well documented regarding disease susceptibility and clinical manifestations. Little is however known about the molecular background to this phenomenon. We herein investigated the conformational stability, amyloid fibrillation kinetics and seeding propensity of different 129-mutants, located in β-strand 1 of PrP (129M (wt), 129A, 129V, 129L, 129W, 129P, 129E, 129K and 129C) in HuPrP90-231. The mutations 129V, 129L, 129K and 129C did not affect stability (midpoints of thermal denaturation, Tm =65-66 °C), whereas the mutants 129A and 129E and the largest side chain 129W were destabilized by 3-4 °C. The most destabilizing substitution was 129P which lowered the Tm by 7.2 °C. All mutants, except 129C, formed amyloid like fibrils within hours during fibril formation under near physiological conditions. Fibril forming mutants, showed a sigmoidal kinetic profile and showed shorter lag times during seeding with preformed amyloid fibrils implicating a nucleated polymerization reaction. In the spontaneous reactions, the lag time of fibril formation was rather uniform for the mutants 129A, 129E, 129V, and 129L resembling the wild type 129M. When the substituted amino acid had a distinct feature discriminating it from the wild type, such as size (129W), positive charge (129K) or rotational constraint (129P), the fibrillation was impeded. 129C did not form ThT/Congo red positive fibrils and non-reducing SDS PAGE of 129C during fibrillation conditions at different time points revealed covalent dimer formation already 15 minutes after fibrillation reaction initiation. Position 129 appears to be a key site for dictating PrP receptiveness towards recruitment into the amyloid state.

The role of the polymorphism 129M/V in the human prion protein is well documented regarding disease susceptibility and clinical manifestations. Little is however known about the molecular background to this phenomenon. We herein investigated the conformational stability, amyloid fibrillation kinetics and seeding propensity of different 129-mutants, located in β-strand 1 of PrP (129M (wt), 129A, 129V, 129L, 129W, 129P, 129E, 129K and 129C) in HuPrP90-231. The mutations 129V, 129L, 129K and 129C did not affect stability (midpoints of thermal denaturation, Tm =65-66 °C), whereas the mutants 129A and 129E and the largest side chain 129W were destabilized by 3-4 °C. The most destabilizing substitution was 129P which lowered the Tm by 7.2 °C. All mutants, except 129C, formed amyloid like fibrils within hours during fibril formation under near physiological conditions. Fibril forming mutants, showed a sigmoidal kinetic profile and showed shorter lag times during seeding with preformed amyloid fibrils implicating a nucleated polymerization reaction. In the spontaneous reactions, the lag time of fibril formation was rather uniform for the mutants 129A, 129E, 129V, and 129L resembling the wild type 129M. When the substituted amino acid had a distinct feature discriminating it from the wild type, such as size (129W), positive charge (129K) or rotational constraint (129P), the fibrillation was impeded. 129C did not form ThT/Congo red positive fibrils and non-reducing SDS PAGE of 129C during fibrillation conditions at different time points revealed covalent dimer formation already 15 minutes after fibrillation reaction initiation. Position 129 appears to be a key site for dictating PrP receptiveness towards recruitment into the amyloid state.

Citations

9 citations in Web of Science®
8 citations in Scopus®
Google Scholar™

Altmetrics

Downloads

59 downloads since deposited on 06 Jul 2012
22 downloads since 12 months
Detailed statistics

Additional indexing

Item Type:Journal Article, refereed, original work
Communities & Collections:04 Faculty of Medicine > University Hospital Zurich > Institute of Neuropathology
Dewey Decimal Classification:570 Life sciences; biology
610 Medicine & health
Language:English
Date:2012
Deposited On:06 Jul 2012 07:05
Last Modified:05 Apr 2016 15:51
Publisher:American Society for Biochemistry and Molecular Biology
ISSN:0021-9258
Additional Information:This research was originally published in Nystrom, Sofie; Mishra, Rajesh; Hornemann, Simone; Aguzzi, Adriano; Nilsson, K Peter R; Hammarstrom, Per (2012). Multiple substitutions of methionine 129 in human prion protein reveal its importance in the amyloid fibrillation pathway. Journal of Biological Chemistry:Epub ahead of print. © the American Society for Biochemistry and Molecular Biology.
Publisher DOI:10.1074/jbc.M112.372136
PubMed ID:22669942
Permanent URL: http://doi.org/10.5167/uzh-63075

Download

[img]
Preview
Content: Accepted Version
Filetype: PDF
Size: 1MB
View at publisher

TrendTerms

TrendTerms displays relevant terms of the abstract of this publication and related documents on a map. The terms and their relations were extracted from ZORA using word statistics. Their timelines are taken from ZORA as well. The bubble size of a term is proportional to the number of documents where the term occurs. Red, orange, yellow and green colors are used for terms that occur in the current document; red indicates high interlinkedness of a term with other terms, orange, yellow and green decreasing interlinkedness. Blue is used for terms that have a relation with the terms in this document, but occur in other documents.
You can navigate and zoom the map. Mouse-hovering a term displays its timeline, clicking it yields the associated documents.

Author Collaborations