A study on the functional importance of the inner space of the extracellular domain in a peptide-gated Na+ channel

2017 Fiscal Year Final Research Report

• Project/Area Number: 15K07149
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Research Field: Animal physiology/Animal behavior
• Research Institution: Hiroshima University
• Principal Investigator: FURUKAWA YASUO 広島大学, 総合科学研究科, 教授 (40209169)
• Project Period (FY): 2015-04-01 – 2018-03-31
• Keywords: イオンチャネル / ペプチド / 構造機能相関

Outline of Final Research Achievements

To understand the function of negative-ring structures by D552 and D556 of the Aplysia FMRFamide-gated Na+ channel (AkFaNaC), the mutant channels (D552N, D556N, D552ND556N) were made and examined in Xenopus oocytes. We found that the Ca2+ coordination to D552 and D556 inhibits the activation of FaNaC. We constructed an allosteric model in which the channels are in either Ca2+-unbound or Ca2+-bound states. The model explains many aspects of the activation of AkFaNaC. To extend the research, we examined seven SS bonds in the external domain of FaNaC which must be important for maintaining the inner space of the external domain of FaNaC. We also started to analyze the functional impact of the negative-rings of the rat acid-sensing ion channel which are structurally similar to the negative-rings of FaNaC.

Free Research Field

神経生物学