Toward developing a molecular toolkit of membrane potential oscillation based on VSP activity

2015 Fiscal Year Final Research Report

• Project/Area Number: 26670102
• Research Category: Grant-in-Aid for Challenging Exploratory Research
• Allocation Type: Multi-year Fund
• Research Field: General physiology
• Research Institution: Osaka University
• Principal Investigator: OKAMURA YASUSHI 大阪大学, 医学(系)研究科(研究院), 教授 (80201987)
• Project Period (FY): 2014-04-01 – 2016-03-31
• Keywords: イオンチャネル / 膜電位

Outline of Final Research Achievements

In this project, we aimed to explore the possibility of developing a molecular toolkit to confer cell autonomous oscillating property of membrane potential based on the molecular mechanisms of phosphoinositide dependence of a combination of distinct ion channels together with expression of voltage-sensing phosphatase that dephosphorylates phosphoinositides. Mouse HCN2 was coexpressed with Ci-VSP RNA in Xenopus oocyte. G-V curve was shifted by 20 mV leftward with reduced conductance upon activities of Ci-VSP in a reversible manner. This clearly shows that VSP activity can regulate HCN channel thus providing a possibility that combination of VSP and HCN channel will serve as a component of an autonomous oscillating molecular tool kit. Since a shift of G-V curve was variable from cell to cell probably dependent on sensitivity of HCN channel to a level of cAMP, it is needed to test with cAMP insensitive mutant of HCN channel.

Free Research Field

生理学