Selective Incorporation of Polyanionic Molecules into Hamster Prions

The central pathogenic event of prion disease is the conformational conversion of a host protein, PrPC, into a pathogenic isoform, PrPSc. We previously showed that the protein misfolding cyclic amplification (PMCA) technique can be used to form infectious prion molecules de novo from purified native...

Full description

Saved in:
Bibliographic Details
Published in:The Journal of biological chemistry 2007-12, Vol.282 (50), p.36341-36353
Main Authors: Geoghegan, James C., Valdes, Pablo A., Orem, Nicholas R., Deleault, Nathan R., Williamson, R. Anthony, Harris, Brent T., Supattapone, Surachai
Format: Article
Language:English
Subjects:
Amyloid - chemistry
Amyloid - metabolism
Animals
Catalysis
Cricetinae
Cricetulus
Female
Male
Polymers - chemistry
Polymers - metabolism
PrPC Proteins - chemistry
PrPC Proteins - metabolism
PrPSc Proteins - chemistry
PrPSc Proteins - metabolism
Ribonucleases - chemistry
RNA - chemistry
RNA - metabolism
Scrapie - metabolism
Scrapie - pathology
Citations: Items that this one cites
Items that cite this one
Online Access:Get full text
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:The central pathogenic event of prion disease is the conformational conversion of a host protein, PrPC, into a pathogenic isoform, PrPSc. We previously showed that the protein misfolding cyclic amplification (PMCA) technique can be used to form infectious prion molecules de novo from purified native PrPC molecules in an autocatalytic process requiring accessory polyanions (Deleault, N. R., Harris, B. T., Rees, J. R., and Supattapone, S. (2007) Proc. Natl. Acad. Sci. U. S. A. 104, 9741-9746). Here we investigated the molecular mechanism by which polyanionic molecules facilitate infectious prion formation in vitro.Ina PMCA reaction lacking PrPSc template seed, synthetic poly(A) RNA molecules induce hamster (Ha)PrPC to adopt a protease-sensitive, detergent-insoluble conformation reactive against antibodies specific for PrPSc. During PMCA, labeled nucleic acids form nuclease-resistant complexes with HaPrP molecules. Strikingly, purified HaPrPC molecules subjected to PMCA selectively incorporate an ∼1-2.5-kb subset of [32P]poly(A) RNA molecules from a heterogeneous mixture ranging in size from ∼0.1 to >6 kb. Neuropathological analysis of scrapie-infected hamsters using the fluorescent dye acridine orange revealed that RNA molecules co-localize with large extracellular HaPrP aggregates. These findings suggest that polyanionic molecules such as RNA may become selectively incorporated into stable complexes with PrP molecules during the formation of native hamster prions.
ISSN:0021-9258
1083-351X
DOI:10.1074/jbc.M704447200