2023 Fiscal Year Final Research Report
The development of molecular design to inhibit the amyloid fibrillation by inhibiting the reversible oligomerization at high temperature with a single residue mutation
| Project/Area Number |
21K15049
|
|---|
| Research Category |
Grant-in-Aid for Early-Career Scientists
|
| Allocation Type | Multi-year Fund |
|---|
| Review Section |
Basic Section 43040:Biophysics-related
|
|---|
| Research Institution | Nagaoka University of Technology |
|---|
Principal Investigator |
|
|---|
| Project Period (FY) |
2021-04-01 – 2024-03-31
|
| Keywords | 蛋白質工学 / アミロイド線維 / 蛋白質凝集 / DSC測定 / 一残基置換 |
|---|
| Outline of Final Research Achievements |
In this study, the complex thermal denaturation process of small globular proteins was examined to precisely inhibit amyloid fibrils, which are known to cause cytotoxicity and neurodegenerative diseases. Detailed calorimetric studies have revealed that reversible oligomer (RO) formation is the early stage of thermal aggregation. Surprisingly, RO was significantly inhibited by single-residue substitution. In the case of PSD95-PDZ3, which is derived from a scaffold protein of postsynaptic thickening, hydrophobic amino acids located at the interface of crystallographic oligomers were determined to play a key role in RO formation. Furthermore, single substitutions with hydrophilic amino acids (F340A and L342A) resulted in significant inhibition of RO at high temperatures, as confirmed by simplified DSC thermograms, and the suppression of amyloid fibril maturation was confirmed by TEM observation.
|
| Free Research Field |
蛋白質工学
|
| Academic Significance and Societal Importance of the Research Achievements |
本研究で考案した一残基置換による分子設計法では、モデル蛋白質の本来の構造・機能に殆ど影響することなく、高温でのRO形成だけを阻害することで、アミロイド線維をはじめとする蛋白質の熱凝集を効果的に抑制できることが示された。今後はより多くのモデル蛋白質で同様の傾向を示せれば、蛋白質凝集を人工的に抑制するための汎用的な手法としての活躍が期待される。また本研究では、逆に疎水性アミノ酸へ一残基置換することで、アミロイド線維が人工的に形成されることも発見した。よってRO形成には、一残基レベルの局所的な疎水性相互作用が駆動力となる仮説が立てられ、蛋白質凝集のメカニズム解明に向けた学術的意義も見出された。
|
