Formation of actin nuclei for poltmerization

2014 Fiscal Year Final Research Report

• Project/Area Number: 23570200
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Research Field: Biophysics
• Research Institution: University of Hyogo (2013-2014); The Institute of Physical and Chemical Research (2011-2012)
• Principal Investigator: ODA Toshiro 兵庫県立大学, 生命理学研究科, 研究員 (20321739)
• Co-Investigator(Renkei-kenkyūsha): AIHARA Tomoki 理化学研究所, 放射光科学総合研究センター, 研究員 (70455327)
• Research Collaborator: WAKABAYASHI Katsuzo 大阪大学, 名誉教授
• Project Period (FY): 2011-04-28 – 2015-03-31
• Keywords: アクチン / 時分割X線小角散乱 / 核形成

Outline of Final Research Achievements

Actin nucleators generate new actin filaments at proper place and timing in eukaryotic cell. The nucleators are crucial for the cell motility driven by a cycle of polymerization - depolymerization of actin. Arp2/3 complex and formin are famous as a nucleator, and a new type of nucleators has been discovered recently. However, the mechanism for generation of new filament remains elusive. To address the mechanism, it should be important to compare the nucleation of actin alone with the nucleation by nucleator, but the nucleation of actin alone also remains elusive. We studied the nucleation of actin alone by the use of the time revolved X-ray small angle scattering. We found that the step from dimer to tetrameter has the largest energetic barrier in the whole polymerization of actin, and that the nucleus is a tetrameter. Nucleators appear to evade the step of actin by each strategy.

Free Research Field

生物物理