Roles of lipid anchors and minor components in domain formation in biomembranes

2020 Fiscal Year Final Research Report

• Project/Area Number: 19K22257
• Research Category: Grant-in-Aid for Challenging Research (Exploratory)
• Allocation Type: Multi-year Fund
• Review Section: Medium-sized Section 37:Biomolecular chemistry and related fields
• Research Institution: Osaka University
• Principal Investigator: Murata Michio 大阪大学, 理学研究科, 教授 (40183652)
• Project Period (FY): 2019-06-28 – 2021-03-31
• Keywords: 脂質ラフト / アシル化タンパク質 / 翻訳後修飾 / 境界脂質 / マイクロドメイン

Outline of Final Research Achievements

In this study, I investigated the role of protein lipid anchors and trace lipids in the domain formation of biological membranes by chemical methods. In domains such as lipid rafts occurring in biological membranes, it is also known that trace lipids induce domain formation by an unknown mechanism, but there are few examples of chemical studies. In this study, as an example of this, when two acyl chains introduced near the N-terminal of Lyn, a protein kinase, bind to a lipid membrane; and when a trace lipid present in only a few mol% affects domain formation, For these two cases, the motility of acyl chains and rare lipids was measured in detail using a model lipid bilayer membrane. As a result, interesting results were obtained on the motility and domain formation of the acyl chains.

Free Research Field

生物物理化学

Academic Significance and Societal Importance of the Research Achievements

翻訳後修飾によってタンパク質に導入された少数のアシル鎖や数モル%しか存在しない希少脂質がドメイン形成など膜の相状態に与える影響については、今まで精密な測定がなされていなかった。本研究では、２本のアシル鎖が結合したタンパク質キナーゼLyn、および糖鎖を有する希少脂質に着目して、膜物性に与える影響を明らかにすることができた。すなわち、学術的意義としては、生物・医学分野で盛んに行われている生体モデル膜系の実験において、希少脂質の影響が無視できないことを定量的に示めすことによって、膜組成を決める上での指針をある程度示すことが出来たと考えている。