Development of a theory to describe ion permeation and selectivity through potassium channels

2015 Fiscal Year Final Research Report

• Project/Area Number: 26870232
• Research Category: Grant-in-Aid for Young Scientists (B)
• Allocation Type: Multi-year Fund
• Research Field: Functional biochemistry; Physical chemistry
• Research Institution: University of Fukui
• Principal Investigator: Sumikama Takashi 福井大学, 医学部, 特命助教 (30579412)
• Project Period (FY): 2014-04-01 – 2016-03-31
• Keywords: イオンチャネル / イオン透過 / イオン選択性 / 分子動力学法 / シミュレーション / モデルチャネル

Outline of Final Research Achievements

Ion selectivity and ion transports through ion channels are essential for life: Living cells generate electrical signals by utilizing selective ion permeation through channels. The aim of this study is to reveal the relationship between ion selectivity and ion permeation. The electrophysiological measurement employing the punch through method implies that the shape of the current-voltage (i-V) curve differs among ion species. In order to explain this difference, the relationship between the shape of i-V curve and the rate-determining step of ion permeation was analyzed by using the molecular dynamics simulation. The shape of the i-V curve of sodium ions through the potassium channel was predicted to be superlinear, which is considered to contribute to the selectivity for potassium over sodium at low voltage.

Free Research Field

生物物理学