Analysis of dynamical structurs of ion channel in native membrane

2015 Fiscal Year Final Research Report

• Project/Area Number: 26670105
• Research Category: Grant-in-Aid for Challenging Exploratory Research
• Allocation Type: Multi-year Fund
• Research Field: General physiology
• Research Institution: National Institute for Physiological Sciences
• Principal Investigator: MURATA Kazuyoshi 生理学研究所, 脳機能計測・支援センター, 准教授 (20311201)
• Co-Investigator(Kenkyū-buntansha): KUNIYASU Akihiko 祟城大学, 薬学部, 教授 (90241348)
• Project Period (FY): 2014-04-01 – 2016-03-31
• Keywords: 膜タンパク質 / クライオ電子顕微鏡 / イオンチャネル / トモグラフィー

Outline of Final Research Achievements

In this study, we attempted to analyze the structure of Ryanodine receptor (RyR), Ca2+ release channel in native sarcoplasmic reticulum (SR) membrane using Zernike phase contrast cryo-electron tomography (ZPC-cryoET), and to reveal the dynamics and the associations with cooperative molecules. SR purified with a mild condition where RyR kept the enzymatic activity showed the large protrusive density on the membrane surface. The density showed a regular square shape representing the homo-tetoramer structure of RyR. A cryo-electron microscopy map of RyR was well fitted into the density, suggesting that it was the RyR structure in the native membrane. Currently, the resolution is limited. Collecting and averaging more data will improve the resolution in in the future, enabling to reveal the dynamical structure and associations with cooperative molecules.

Free Research Field

構造生物学