Conformational Properties of Prion Strains Can Be Transmitted to Recombinant Prion Protein Fibrils in Real-Time Quaking-Induced Conversion

• Sano, Kazunori

• Atarashi, Ryuichiro

• Ishibashi, Daisuke

• Nakagaki, Takehiro

• Satoh, Katsuya

• Nishida, Noriyuki

• B. W. Caughey

  editor

Abstract

The phenomenon of prion strains with distinct biological characteristics has been hypothesized to be involved in the structural diversity of abnormal prion protein (PrPSc). However, the molecular basis of the transmission of strain properties remains poorly understood. Real-time quaking-induced conversion (RT-QUIC) is a cell-free system that uses Escherichia coli-derived recombinant PrP (rPrP) for the sensitive detection of PrPSc. To investigate whether the properties of various prion strains can be transmitted to amyloid fibrils consisting of rPrP (rPrP fibrils) using RT-QUIC, we examined the secondary structure, conformational stability, and infectivity of rPrP fibrils seeded with PrPSc derived from either the Chandler or the 22L strain. In the first round of the reaction, there were differences in the secondary structures, especially in bands attributed to β-sheets, as determined by infrared spectroscopy, and conformational stability between Chandler-seeded (1st-rPrP-fibCh) and 22L-seeded (1st-rPrP- fib22L) rPrP fibrils. Of note, specific identifying characteristics of the two rPrP fibril types seen in the β-sheets resembled those of the original PrPSc. Furthermore, the conformational stability of 1st-rPrP-fibCh was significantly higher than that of 1strPrP- fib22L, as with Chandler and 22L PrPSc. The survival periods of mice inoculated with 1st-rPrP-fibCh or 1st-rPrP-fib22L were significantly shorter than those of mice inoculated with mixtures from the mock 1st-round RT-QUIC procedure. In contrast, these biochemical characteristics were no longer evident in subsequent rounds, suggesting that nonspecific uninfected rPrP fibrils became predominant probably because of their high growth rate. Together, these findings show that at least some strainspecific conformational properties can be transmitted to rPrP fibrils and unknown cofactors or environmental conditions may be required for further conservation.

Journal of Virology, 88(20), pp.11791-11801; 2014

Journal

• Journal of Virology

  Journal of Virology 88 (20), 11791-11801, 2014-10

  American Society for Microbiology

Keywords

• Virology
• Insect Science
• Immunology
• Microbiology

Details

• CRID: 1050005822286925184
• NII Article ID: 120006986372
• ISSN: 0022538X
• ISSN: 10985514
• DOI: 10.1128/jvi.00585-14
• HANDLE: 10069/34914
• Web Site: https://nagasaki-u.repo.nii.ac.jp/records/5826
• Web Site: https://journals.asm.org/doi/pdf/10.1128/JVI.00585-14
• Text Lang: en
• Article Type: journal article
• Data Source:
  • IRDB
  • Crossref
  • CiNii Articles
  • KAKEN