NR AXQE
AU Korth,C.; Leliveld,R.; Stitz,L.
TI Synthetic Prions from Recombinant Mouse Prion Protein with an Expanded Octarepeat Domain
QU International Conference - Prion 2007 (26.-28.9.2007) Edinburgh International Conference Centre, Edinburgh, Scotland, UK - Book of Abstracts: Oral Abstracts FC1.5
IA http://www.prion2007.com/pdf/Prion Book of Abstracts.pdf
PT Konferenz-Vortrag
AB
The idea of infectious proteins implies that protein conformations can be generated in vitro and de novo without prior contact to existing PrPsc templates. It has been reported that in vitro generated synthetic prions with a deleted N-terminus (PrP89-231) were infectious in a transgenic mouse model overexpressing the same N-terminally deleted PrP construct PrP89-231.
Here, we set out to demonstrate infectivity of an E. coli-expressed recombinant mouse PrP construct with a mutation corresponding to a human genetic PrnP mutation leading to an expanded octarepeat domain. We had previously shown that the expanded OR domain had particular affinity for PrPsc and an inherent multimerization tendency.
Recombinant mouse PrP and mouse PrP with 10 additional octarepeats (moPrP14OR) were expressed in Escherichia coli and purified via IMAC columns. Refolding was done with different protocols. Recombinant proteins were passaged into mouse PrP overexpressing tg20 mice.
We report on cases coming down with prion disease after inoculation with moPrP14OR but not wild-type moPrP in the second passage after > 140 days, demonstrating a species barrier-like effect with shortening of incubation time to 60 days on the third passage.
MoPrP14OR is thus able to induce a self-perpetuating process of non-mutant PrP conversion to PrPsc, although with poor initial efficiency. Part of this inefficient prion initiation maybe due to a species barrier-like effect due to non-homologous sequences of donor and host PrP species. We will discuss how the biophysical characteristics of expanded OR could initiate and template this process.
AD C. Korth, R. Leliveld, Heinrich Heine University Duesseldorf, Neuropathology, Germany; L. Stitz, Friedrich-Löffler Institute, Germany
SP englisch
PO Schottland