Roles of CP for actin polymerization to regulate cell protrusions

2017 Fiscal Year Final Research Report

• Project/Area Number: 15K21106
• Research Category: Grant-in-Aid for Young Scientists (B)
• Allocation Type: Multi-year Fund
• Research Field: Nanobioscience; Biophysics
• Research Institution: Nagoya Institute of Technology
• Principal Investigator: Fujiwara Ikuko 名古屋工業大学, 工学(系)研究科(研究院), 助教 (10742075)
• Co-Investigator(Renkei-kenkyūsha): HAMMER John National Institutes of Health(NIH), National Heart, Lung and Blood Institute(NHLBI), 主任
• Research Collaborator: POLLARD Thomas Yale University, Department of Molecular Cellular and Developmental Biology, 教授 ; COURTEMANCHE Naomi University of Minnesota, Department of Genetics, Cell Biology and Development, 独立助教 ; KANDORI Hideki 名古屋工業大学, 工学研究科, 教授 (70202033) ; TSUNODA Satoshi 名古屋工業大学, 工学研究科, 特任准教授 さきがけ研究者 (10158983) ; MAEDA Yuichiro 名古屋大学, 理学研究科, 特任教授 (10321811) ; TAKEDA Shuichi 名古屋大学, 理学研究科, 研究員 (50509081) ; ODA Toshiro 名古屋大学, 理学研究科, 教授 (20321739)
• Project Period (FY): 2015-04-01 – 2018-03-31
• Keywords: アクチン / 細胞運動 / 細胞骨格 / アクチン制御メカニズム

Outline of Final Research Achievements

Actin polymerization is essential for cell motility, and some proteins bind to the fast growing end of actin filaments (B-end) and regulate actin elongation rate. This project has focused on Capping Protein (CP) and its regulator CARMIL, which domain called CAH3 is crucial for CP binding. To understand the molecular regulatory mechanism of CARMIL to CP, a point mutation of D44 of CP (beta)-subunit was used, which is important for CARMIL binding. Pyrene assay showed that CP(beta)D44N has a strong capping activity as same as CP wild type (CPwt). Both pull down and ITC assays showed that CP(beta)D44N has ~50 fold weaker bind affinity to CAH3 than CPwt. The CAH3 driven uncapping and the capping activity of the complex of CP(beta)D44N: CAH3 were monitored by TIRF microscope. Current result suggests that the insufficient binding of CP to CAH3 due to lacking D44 of CP (beta)-subunit causes the long duration time for uncapping.

Free Research Field

生物物理