Study of signal transduction and physiological role for the formation of lipid domaines

2018 Fiscal Year Final Research Report

• Project/Area Number: 16K15056
• Research Category: Grant-in-Aid for Challenging Exploratory Research
• Allocation Type: Multi-year Fund
• Research Field: Integrative animal science
• Research Institution: Kagoshima University
• Principal Investigator: Fujita Akikazu 鹿児島大学, 農水産獣医学域獣医学系, 教授 (60282232)
• Project Period (FY): 2016-04-01 – 2019-03-31
• Keywords: 脂質 / 脂肪 / 微細局在 / 電子顕微鏡 / オートファジー / 酵母 / 急速凍結 / 凍結割断

Outline of Final Research Achievements

Phosphatidylinositol 4-phosphate (PtdIns(4)P) itself has been found to serve as an essential signalling molecule in the cell organelles where it is involved in the control of membrane trafficking, and signal transduction pathways, via direct interaction with PtdIns(4)P-binding protein. To completely understand the autophagy, it is important to determine the localization of PtdIns(4)P in the autophagosome. To analyze the distribution of PtdIns(4)P at a nanoscale, we employed the quick-freezing and freeze-fracture replica labeling (QF-FRL) method. We found that the localization of PtdIns(4)P in the luminal leaflet in the biological membrane. We also showed using mutant yeast cells that PtdIns 4-kinases Pik1p and Stt4p have essential roles in the autophagosome formation and autophagosome-vacuole fusion in yeast, respectively.

Free Research Field

細胞生物学

Academic Significance and Societal Importance of the Research Achievements

私たちは脂質を観る新たな技術（急速凍結・凍結割断レプリカ標識法）を開発し、電子顕微鏡を用いて生体膜における微細構造レベルでの膜脂質の分布解析を可能にした。この技術は膜脂質の機能解明に大きく貢献し、生命機能解明への新たなアプローチを提供できると考えている。さらにこのアプローチによりもたらされた知見は、脂質代謝異常をはじめ様々な疾患の原因や病態の解明に役立つものと期待している。