A novel mechanism of organelle fission through the internal structure of mitochondria

2021 Fiscal Year Final Research Report

• Project/Area Number: 20K22662
• Research Category: Grant-in-Aid for Research Activity Start-up
• Allocation Type: Multi-year Fund
• Review Section: 0702:Biology at cellular to organismal levels, and related fields
• Research Institution: Rikkyo University
• Principal Investigator: Kawanami (Akabane) Shiori (赤羽しおり) 立教大学, 理学部, 助教 (70793355)
• Project Period (FY): 2020-09-11 – 2022-03-31
• Keywords: ミトコンドリア / ミトコンドリア分裂 / ミトコンドリア内膜構造

Outline of Final Research Achievements

Mitochondria, double-membrane bounded organelles, maintain normal function by dynamically changing their membrane structure. In this study, we investigated the mechanisms of mitochondrial fission, focusing on autonomously regulation via the internal structure of mitochondria, in order to understand coordination between fission and the internal structure of double-membrane bounded organelles. We analyzed mitochondrial function under hypoxia, physiological conditions that induce mitochondrial fission. Under hypoxia, aggregated proteins were detected in the mitochondrial matrix, and stress-inducible transcription factors were highly expressed. These results indicated that stress response is induced by protein aggregation under hypoxia, suggesting that stress response pathways are involved in mitochondrial fission.

Free Research Field

細胞生物学

Academic Significance and Societal Importance of the Research Achievements

これまでのミトコンドリア分裂の研究はすべて、細胞質からの作用による外膜からの切断に着目したものであり、分裂時における内膜構造の変化は考慮されてこなかった。また、分裂時における膜融合因子やクリステ構造形成因子の役割を検討した報告はなく、本研究が先駆けて行うアプローチである。本研究は、内部からの自律的な制御に着目してミトコンドリア分裂機構を解明することで、ミトコンドリア分裂の全体像を明らかにするとともに、様々な生物種の二重膜オルガネラにおける分裂の生理的意義の理解につながると考えられる。