Monolayers to Bilayers to Membranes

单层膜到双层膜

• 批准号: 9603092
• 负责人: Harden McConnell
• 金额: $ 33万
• 依托单位: Stanford University
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 1997
• 资助国家: 美国
• 起止时间: 1997-03-01 至 2001-02-28
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=9603092&HistoricalAwards=false
• 关键词: Monolayers; Bilayers; Membranes

9603092 McConnell This research seeks to study putative liquid-liquid phase separations in lipid bilayer membranes, and their possible role in the function of biological membranes. The approach to these problems relies heavily on the previous finding in this laboratory of liquid-liquid phase separations in lipid monolayer membranes. The interest in liquid-liquid phase separations (along with their critical point properties) stems from their possible role in biological membranes, including membrane fusion, shape, trans membrane asymmetries, as well as enzymatic regulation of lipid composition. A major challenge in this work is to demonstrate unequivocally a one liquid to two liquid phase transition in a lipid bilayer membrane. A second challenge is to investigate the possibility that such transitions play a role in the regulation of lipid composition of biological membranes in response to physical or chemical factors (e.g., temperature or hormones). The techniques to be used in these studies rely heavily on fluorescence microscopy. The membrane that surrounds a living cell is very much like a very thin, two dimensional liquid. This liquid is quite complex being composed of many sorts of lipid molecules that together form this two-dimensional membrane. There is much experimental evidence that the physical properties and chemical compositions of these membranes are carefully regulated in living cells, but the relationship between the physical and chemical properties is very poorly understood, as is the role of these properties in the function of cells. The goal is to find out if liquid-liquid phase separations exist in these membrane liquids, and if they serve important biological functions.

9603092 McConnell这项研究旨在研究脂质双层膜中假定的液-液相分离，以及它们在生物膜功能中的可能作用。解决这些问题的方法在很大程度上依赖于本实验室以前在脂质单层膜中的液-液相分离的发现。对液-液相分离（沿着其临界点性质）的兴趣源于它们在生物膜中的可能作用，包括膜融合、形状、跨膜不对称性以及脂质组成的酶调节。在这项工作中的一个主要挑战是明确地证明一个液体到两个液体在脂质双层膜的相变。第二个挑战是研究这样的转变在响应物理或化学因素（例如，温度或激素）。这些研究中使用的技术严重依赖于荧光显微镜。 围绕在活细胞周围的膜非常像一种非常薄的二维液体。这种液体是相当复杂的，由许多种类的脂质分子组成，这些脂质分子一起形成这种二维膜。有许多实验证据表明，这些膜的物理性质和化学成分在活细胞中受到仔细调节，但物理和化学性质之间的关系知之甚少，这些性质在细胞功能中的作用也是如此。目的是找出这些膜液体中是否存在液-液相分离，以及它们是否具有重要的生物功能。