Nanoscale structure of lipid membrane and its role in membrane-mediated interactions

脂质膜的纳米结构及其在膜介导的相互作用中的作用

• 批准号: RGPIN-2017-05030
• 负责人: Leonenko, Zoya
• 金额: $ 5.25万
• 依托单位: University of Waterloo
• 依托单位国家: 加拿大
• 项目类别: Discovery Grants Program - Individual
• 财政年份: 2019
• 资助国家: 加拿大
• 起止时间: 2019-01-01 至 2020-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=691651
• 关键词: Nanoscale; structure; lipid; membrane; its

Cellular membrane is a fundamental unit of life and consists of nanoscopic, highly dynamic rafts composed of condensed lipids, cholesterol, and membrane proteins. These rafts are a major aspect of cell organization and central to the communication of cells with their environs. Real biological membranes are very complex and synthetic lipid bilayers or model lipid membranes are therefore widely used to mimic them in biophysical studies. ******The main goals of my research program are two-fold: 1) to discover novel phenomena in the biophysics of model lipid membranes, design complex and biologically relevant model membranes and elucidate the molecular mechanism of membrane interactions with charged peptides. This will provide a fundamental platform for understanding the molecular mechanism of amyloid toxicity in Alzheimer's disease (AD) and the mechanism of antimicrobial action; and 2) to develop novel membrane-based biosensing platforms, by merging lipid membrane with nanofabricated plasmonic substrates. ******Studying the nanoscale structure of model membranes, which mimic neuronal membranes are important for the understanding of the molecular mechanisms of amyloid binding to the membrane and amyloid toxicity in AD. I propose to investigate the similarities and differences between amyloid and antimicrobial peptides in order to expose the fundamental molecular mechanisms of their interactions with lipid membranes. My group will elucidate the effects of lipid composition and cholesterol that induce domain formation and change electrostatic heterogeneity in the lipid membrane. To tackle these problems, we will combine atomic force microscopy (AFM), atomic force spectroscopy (AFS), frequency modulation Kelvin probe force microscopy (FM-KPFM), Black Lipid Membrane (BLM) and plasmonics methods, including surface Plasmon resonance (SPR) and surface enhanced Raman spectroscopy (SERS). These advanced physical methods will be used to test my hypothesis that the membrane nanoscale structure is a dynamic property which plays an active and decisive role in its interactions with charged peptides. We will develop protocols to attach model lipid membrane to metallic nanostructured substrates and use SPR and SERS methods to monitor real time peptide-lipid interactions quantitatively and with high sensitivity. This will open new directions in biosensing applications allowing for monitoring membrane proteins interactions for various applications.******The proposed research program will advance knowledge in the areas of membrane biophysics, will provide further insight into the role of nanoscale membrane structure in amyloidal and antimicrobial peptides action and will serve as platform for the development of novel biosensors for protein detection. Furthermore, my research program will provide an excellent interdisciplinary training opportunity for multiple trainees of all levels.***********

细胞膜是生命的基本单位，由纳米级的、高度动态的筏组成，筏由浓缩的脂质、胆固醇和膜蛋白组成。这些筏是细胞组织的一个主要方面，也是细胞与周围环境交流的中心。真实的生物膜非常复杂，因此在生物物理研究中广泛使用合成脂质双层或模型脂质膜来模拟它们。* 我的研究计划的主要目标是双重的：1）发现模型脂质膜的生物物理学中的新现象，设计复杂的和生物相关的模型膜，并阐明膜与带电肽相互作用的分子机制。这将为理解阿尔茨海默病（AD）中淀粉样蛋白毒性的分子机制和抗菌作用机制提供基础平台; 2）通过将脂质膜与纳米制造的等离子体基质合并，开发新型基于膜的生物传感平台。** 研究模拟神经元膜的模型膜的纳米级结构对于理解AD中淀粉样蛋白与膜结合和淀粉样蛋白毒性的分子机制非常重要。我建议研究淀粉样蛋白和抗菌肽之间的相似性和差异，以揭示它们与脂质膜相互作用的基本分子机制。我的小组将阐明脂质成分和胆固醇的影响，诱导域的形成和改变脂质膜的静电异质性。为了解决这些问题，我们将结合联合收割机原子力显微镜（AFM），原子力光谱（AFS），调频开尔文探针力显微镜（FM-KPFM），黑脂膜（BLM）和等离子体方法，包括表面等离子体共振（SPR）和表面增强拉曼光谱（Sers）。这些先进的物理方法将被用来测试我的假设，即膜的纳米结构是一个动态的属性，在其与带电肽的相互作用中起着积极的和决定性的作用。我们将开发将模型脂质膜附着到金属纳米结构基底上的方案，并使用SPR和Sers方法定量和高灵敏度地监测真实的时间肽-脂质相互作用。这将为生物传感应用开辟新的方向，允许监测各种应用的膜蛋白相互作用。拟议的研究计划将推进膜生物物理学领域的知识，将进一步深入了解纳米级膜结构在淀粉样蛋白和抗菌肽作用中的作用，并将作为开发新型蛋白质检测生物传感器的平台。此外，我的研究计划将提供一个很好的跨学科的培训机会，为所有级别的多个学员。*