Cell biological study for the distribution and dynamic of lipid in the biological membrane with nano-scale analyzing techniques

2023 Fiscal Year Final Research Report

• Project/Area Number: 20H03154
• Research Category: Grant-in-Aid for Scientific Research (B)
• Allocation Type: Single-year Grants
• Section: 一般
• Review Section: Basic Section 42020:Veterinary medical science-related
• 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)
• Co-Investigator(Kenkyū-buntansha): 正谷 達謄 岐阜大学, 応用生物科学部, 准教授 (70614072)
• Project Period (FY): 2020-04-01 – 2023-03-31
• Keywords: 脂質 / 電子顕微鏡 / 急速凍結 / フリーズフラクチャー / 微細分布 / オートファジー

Outline of Final Research Achievements

Autophagy has crucial roles in the intracellular metabolisms of various molecules including proteins, nucleotides, and lipids. We investigated roles of lipids transporter Oshp, which can transport PtdSer and PtdIns(4)P between the membranes of intracellular organelles, in the autophagy process of yeast cells. We found that the defect of the autophagic activity in the all osh genes (osh1-osh7)-knocked out yeast. It was found that no autophagosome was detected in osh5-deleted mutant and accumulated autophagic bodies in the vacuole in osh4-deleted mutant when autophagy was induced. We suggest that Osh5p and Osh4p have roles in the autophagosome formation and in the degradation of autophagic body in the vacuole, respectively, by transporting PtdSer and PtdIns(4)P between the organelle membranes.

Free Research Field

細胞生物学

Academic Significance and Societal Importance of the Research Achievements

Autophagyは、初期胚発生、細胞変性抑制、細胞内侵入細菌分解、選択的基質分解、がん抑制、炎症制御などの機能を持つことが判明してきた。しかし、autophagosomeがどこで形成、膜脂質の由来は何か、というような基本的なことがわかっていない。今回の研究で得られた成果はautophagyにおける脂質動態の解明に大きく貢献し、オートファジー全容の解明への新たなアプローチを提供する。さらにオートファジー機能の欠陥を原因とする疾患の病態の解明、その成果に基づく新たな医薬品の開発も期待され、ライフイノベーション推進への寄与は大きい。