Spatiotemporal imaging of membrane morphology and protein localization during endocytic process

2017 Fiscal Year Final Research Report

• Project/Area Number: 16K14722
• Research Category: Grant-in-Aid for Challenging Exploratory Research
• Allocation Type: Multi-year Fund
• Research Field: Cell biology
• Research Institution: Kyoto University
• Principal Investigator: Shigehiro Yoshimura 京都大学, 生命科学研究科, 准教授 (90346106)
• Co-Investigator(Renkei-kenkyūsha): ADACHI Taiji 京都大学, ウイルス・再生医科学研究所, 教授 (40243323)
• Project Period (FY): 2016-04-01 – 2018-03-31
• Keywords: エンドサイトーシス / シグナル伝達 / 細胞骨格 / アクチン / クラスリン / 原子間力顕微鏡 / ナノイメージング

Outline of Final Research Achievements

We established hybrid time-lapse imaging system by combining high-speed atomic force microscopy and confocal laser-scanning microscopy to simultaneously image membrane morphology and protein localization during clathrin-mediated endocytosis. Spatiotemporal assembly of proteins such as clathrin, dynamin, epsin and actin, were successfully revealed together with morphological changes of the membrane. The inhibition of actin dynamics affected assembly, maturation and closing steps, suggesting important roles of cortical actin dynamics in multiples steps of endocytic process. At the closing step, most of the pits were covered by a membrane swelling, which is induced by a quick burst of actin polymerization, and then irreversibly closed, whereas some pits were closed without these motions. By combining membrane model and dynamic actin polymerization model, the mechanism of the pit closure was analyzed.

Free Research Field

生物物理