Probing the Dimerization of Transmembrane Helices in Lipid Bilayers

探讨脂质双层中跨膜螺旋的二聚化

• 批准号: 0315663
• 负责人: Kalina Hristova
• 金额: $ 75.23万
• 依托单位: Johns Hopkins University
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2003
• 资助国家: 美国
• 起止时间: 2003-08-15 至 2007-07-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0315663&HistoricalAwards=false
• 关键词: Probing; Dimerization; Transmembrane; Helices; Lipid

AbstractMCB 0315663Biophysical studies of membrane protein dimerization, one of the basic steps in folding and signal transduction, are hindered by the lack of an adequate method to probe dimerization in a model bilayer environment. In this project, the PI will develop a new tool for probing membrane protein dimerization in a lipid bilayer. She will measure the thermodynamics of Glycophorin A dimerization in a lipid environment, and compare the results to previous studies in detergent systems. The method to be developed requires the assembly of surface-attached bilayers containing laterally mobile membrane proteins with identical orientations. The dimerization of the fluorescently labeled proteins will be measured using imaging resonance energy transfer. This project will yield thermodynamic measurements of GpA dimerization in a bilayer environment. In the long term, the method will be a new useful tool in dissecting the chemistry of interactions within membrane proteins in hydrophobic environments. Approximately 20% of all proteins in complex organisms are membrane-associated. Despite their abundance and key roles in cell life, our knowledge of the folding and the structure-function relationship for membrane proteins is limited, and lags far behind that of soluble proteins. In part, this is due to limited biophysical tools to adequately probe the physical-chemical principles underlying membrane protein function. For instance, a method to probe the dimerization of transmembrane helices in the native-like lipid bilayer environment is still missing. In this project, the PI will develop such a method by assembling surface grafted lipid bilayers that contain membrane proteins. Dimerization will be measured using an imaging fluorescence technique. The PI will train two graduate students and enhance the educational experience of underrepresented minority students currently conducting research in her laboratory.

摘要MCB 0315663膜蛋白二聚体的生物物理研究，折叠和信号转导的基本步骤之一，阻碍了缺乏一个适当的方法来探测在一个模型双层环境中的二聚体。 在这个项目中，PI将开发一种新的工具，用于探测脂质双层中的膜蛋白二聚化。 她将测量在脂质环境中血型糖蛋白A二聚化的热力学，并将结果与以前在洗涤剂系统中的研究进行比较。 待开发的方法需要组装含有具有相同取向的横向移动的膜蛋白的表面附着双层。 将使用成像共振能量转移测量荧光标记蛋白质的二聚化。 该项目将产生在双层环境中的GpA二聚化的热力学测量。 从长远来看，该方法将是一个新的有用的工具，在解剖化学的膜蛋白在疏水环境中的相互作用。在复杂生物体中，大约20%的蛋白质是膜相关的。 尽管它们在细胞生命中的丰富和关键作用，我们对膜蛋白的折叠和结构-功能关系的了解是有限的，远远落后于可溶性蛋白。 在某种程度上，这是由于有限的生物物理工具，以充分探测膜蛋白功能的物理化学原理。 例如，一种方法来探测跨膜螺旋的二聚化在天然样的脂质双层环境中仍然是失踪。 在这个项目中，PI将通过组装含有膜蛋白的表面接枝脂质双层来开发这种方法。 将使用成像荧光技术测量二聚化。 PI将培训两名研究生，并加强目前在她的实验室进行研究的代表性不足的少数民族学生的教育经验。