LATERAL MOBILITY OF PLASMA MEMBRANE PROTEINS

我们提出的研究将使用几种不同的测量方法， 特异性膜蛋白的横向移动性，以研究 质膜成分的组织和动力学。一个主要目标 将进一步表征细胞质和细胞外基质 限制动物细胞成分横向移动的因素 膜。 这些限制不仅会影响横向的速率， 扩散，而且在某些情况下， 蛋白质空间结构域。 这些研究将采用一种重要的新工具， 粒子跟踪显微镜，直接可视化的布朗运动， 单个活细胞表面的单个或小的蛋白质组。 建议努力进一步开发和建立这种技术， 包括增强其时间和空间分辨率。 该技术将 应用于仔细表征运动和限制程度 特定的跨膜和脂质连接的膜蛋白。直接 测试“扩散到陷阱”的机制， 提出了细胞膜的结构。 最后，结合 粒子跟踪技术，荧光恢复后， 光漂白和基因转移实验将被应用于测试一个 质膜结构的广义工作假说--瞬时 交互模型。 据估计，这一过程中产生的信息 该项目将最终加深对等离子体的理解 正常和患病状态下的膜组织。

Our proposed studies will use several different measurements of the lateral mobility of specific membrane proteins to study the lateral organization and dynamics of plasma membrane components. A major objective will be to further characterize the cytoplasmic and extracellular matrix factors which restrict the lateral mobility of components of animal cell membranes. These restrictions may affect not only the rate of lateral diffusion but also, in some instances, serve to confine the membrane protein to spatial domains. These studies will employ a major new tool, particle tracking microscopy, to directly visualize Brownian motion of single or small groups of proteins on the surface of single living cells. Efforts are proposed to further develop and establish this technology, including enhancing its time and spatial resolution. The technology will be applied to carefully characterize the motions and degree of confinement of specific transmembrane and lipid-linked membrane proteins. Direct testing of the "diffusion to a trap" mechanism of assembling specific structures in the plasma membrane is proposed. Lastly, a combination of the particle tracking technique, fluorescence recovery after photobleaching and gene transfer experiments will be applied to test a generalized working hypothesis of plasma membrane structure--the Transient Interaction Model. It is anticipated that information generated in this project will ultimately lead to a deepened understanding of plasma membrane organization in normal and diseased states.