Elucidation of the mechanism of spontaneous prion production in sporadic and familial prion diseases

• Project/Area Number: 18K07393
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Review Section: Basic Section 51030:Pathophysiologic neuroscience-related
• Research Institution: University of Miyazaki
• Principal Investigator: IMAMURA MORIKAZU 宮崎大学, 医学部, 准教授 (10391442)
• Project Period (FY): 2018-04-01 – 2021-03-31
• Project Status: Completed (Fiscal Year 2020)
• Budget Amount: ¥4,420,000 (Direct Cost: ¥3,400,000、Indirect Cost: ¥1,020,000); Fiscal Year 2020: ¥1,300,000 (Direct Cost: ¥1,000,000、Indirect Cost: ¥300,000); Fiscal Year 2019: ¥1,300,000 (Direct Cost: ¥1,000,000、Indirect Cost: ¥300,000); Fiscal Year 2018: ¥1,820,000 (Direct Cost: ¥1,400,000、Indirect Cost: ¥420,000)
• Keywords: 孤発性プリオン病 / 遺伝性プリオン病 / プリオン / 試験管内変換 / PMCA / 試験管内プリオン生成 / 補因子 / 異常プリオン蛋白質 / プリオン病

Outline of Final Research Achievements

In this study, we established an in vitro system for efficient spontaneous conversion of recombinant prion protein and recombinant prion protein carrying the causative gene mutation of familial prion diseases into prion-like structures. Bioassays showed that these products actually functioned as prions, and we concluded that we had successfully constructed an in vitro model of solitary and hereditary prion diseases. We also applied this in vitro prion spontaneous generation system to reveal that one of the reasons for the generation of prion strains with different properties is the difference in the composition of cofactors involved in structural transformation.

Academic Significance and Societal Importance of the Research Achievements

本課題では、孤発性および遺伝性プリオン病の試験管内モデルの構築に成功した。この実験系は、未だ明らかになっていない正常プリオン蛋白質からプリオンへの構造変換メカニズムを解明するために非常に有用である。さらに、この実験系はプリオン病の治療・予防薬のスクリーニング系として用いることができる。その他に本課題では、性状が異なるプリオン株が生成する要因のひとつに構造変換に関わる補因子の組成の違いがあることを明らかにした。この結果は、ある一種類の動物種から異なる性状をもつプリオン株が複数生じるメカニズムを解明するための重要な手がかりになると考えられる。

Research Products

• [Journal Article] First case of atypical scrapie in a goat in Japan (2019)
  • Author(s): Matsuura Y, Miyazawa K, Imamura M, Yokoyama T, Iwamaru Y.
  • Journal Title: Journal of Veterinary Medical Science Volume: 81 Issue: 7 Pages: 986-989
  • DOI: 10.1292/jvms.18-0710
  • NAID: 130007677812
  • ISSN: 0916-7250, 1347-7439
  • Peer Reviewed / Open Access
• [Presentation] Isolation of hidden minor prion conformers from classical scrapie isolates in advanced protein misfolding cyclic amplification in the presence of arginine ethyl ester. (2019)
  • Author(s): Imamura M, Miyazawa K, Matsuura Y, Iwamaru Y, Kitamoto T, Mohri S, Takatsuki H, Mori T, Atarashi R
  • Organizer: APPS2019
  • Int'l Joint Research
• [Presentation] Simultaneous addition of digitonin, heparin and arginine ethyl ester improves in vitro amplification of PrPSc derived from various prion strains. (2018)
  • Author(s): Imamura M, Tabeta N, Matsuura Y, Iwamaru Y, Kitamoto T, Ma J, Mohri S, Murayama Y, Takatsuki H, Mori T, Atarashi R
  • Organizer: APPS 2018
  • Int'l Joint Research
• [Presentation] Highly sensitive detection of PrPSc derived from various prion strains by simultaneous addition of digitonin, heparin and arginine ethyl ester to protein misfolding cyclic amplification. (2018)
  • Author(s): Imamura M, Tabeta N, Matsuura Y, Iwamaru Y, Kitamoto T, Ma J, Mohri S, Murayama Y, Takatsuki H, Mori T, Atarashi R
  • Organizer: Prion 2018
  • Int'l Joint Research
• [Presentation] In vitro approach to estimate the human transmission risk of prions (2018)
  • Author(s): Iwamaru Y, Imamura M, Matsuura Y, Miyazawa K, Yokoyama T
  • Organizer: Prion 2018
  • Int'l Joint Research