Cell-free membrane remodeling guided by DNA nano-templates

描述（由申请人提供）：精心安排的膜重塑创造物质和信息流来维持细胞的生命周期。因此，了解细胞用来产生、维持和变形膜结构的分子机制一直是细胞生物学的中心任务。无细胞实验为研究介导细胞膜重塑的生物分子之间的功能相互作用提供了一个干净的系统。然而，以往的体外研究大多缺乏对膜的物理和化学性质的精确控制（如膜囊泡的大小和形状、膜相关蛋白的局部密度和空间组织），从而留下了相当大的模糊性空间。我们假设，我们可以通过高水平的控制来设计膜重塑事件，并通过建立在DNA纳米结构上精确组织膜调节元件的体外场景，进一步阐明细胞膜动力学的分子机制。换句话说，我们计划通过人工地将其天然成分放置在可编程纳米模板上来解剖膜运输机器。我们建议使用这种转化方法来研究SNARE介导的膜融合的潜在机制以及bar结构域蛋白的膜曲率传感/诱导活性。除了本提案设定的目标之外，我们相信我们的项目可以为膜运输相关疾病的新治疗策略以及有效的药物递送纳米机器打开大门。

DESCRIPTION (provided by applicant): Orchestrated membrane remodeling creates flows of substance and information to sustain the lifecycle of a cell. Therefore understanding the molecular mechanisms that cells use to generate, maintain and deform the membrane structures has been a central task of cell biology. Cell-free experiments provide a clean system to study the functional interactions between the biomolecules that mediate the cell membrane remodeling. However, most of previous in vitro studies lack the precise control of the physical and chemical properties of the membrane (e.g. membrane vesicle's size and shape; local density and spatial organization of membrane- associating proteins), thus leaving considerable room of ambiguity. We hypothesize that we could engineer membrane remodeling events with a high level of control and further elucidate the molecular mechanisms for cell membrane dynamics by setting up in vitro scenarios in which the membrane modulating elements are precisely organized on DNA nanostructures. In other words, we plan to dissect the membrane trafficking machineries by artificially placing their natural components on a programmable nano-template. We propose to use this transformative approach to study the underlying mechanism of SNARE mediated membrane fusion as well as the membrane curvature sensing/inducing activities of BAR-domain proteins. Beyond the goals set by this proposal, we believe our project could open doors for new therapeutic strategies for membrane trafficking related diseases as well as efficient drug-delivery nanomachines.