Structure and molecular interactions in aggregation of amyloid beta protein

2015 Fiscal Year Final Research Report

• Project/Area Number: 26860020
• Research Category: Grant-in-Aid for Young Scientists (B)
• Allocation Type: Multi-year Fund
• Research Field: Physical pharmacy
• Research Institution: University of Toyama
• Principal Investigator: Ikeda Keisuke 富山大学, 大学院医学薬学研究部(薬学), 助教 (00553281)
• Project Period (FY): 2014-04-01 – 2016-03-31
• Keywords: アミロイド / 脂質膜 / 膜曲率

Outline of Final Research Achievements

Conversion of amyloid-β (Aβ) protein from a non-toxic monomer into the toxic aggregates is the possible pathogenic pathways in Alzheimer’s disease. Recent studies have suggested that lipid membranes play key roles in protein aggregation. However, the binding modes and the mechanisms of Aβ aggregation on lipid vesicles are not fully understood. Here, we observed that a high positive curvature of lipid vesicles with diameters of ~30 nm enhanced the binding of Aβ with anionic membranes in the liquid crystalline phase and with zwitterionic membranes in the gel phase. The binding modes of Aβ to these membranes differ in terms of the depth of the protein in the membrane and of the protein structure. Amyloid fibril formation of Aβ was accelerated in the presence of the vesicles. Our findings suggest that packing defects on membranes with high curvatures might result in the accumulation of toxic protein aggregates.

Free Research Field

生物物理化学