Abstract：
Cell-specific aptamers offer a powerful tool to study membrane receptors at the single-molecule level. Most target receptors of aptamers are highly expressed on the cell surface, but difficult to analyze in situ because of dense distribution and fast velocity. Therefore, we herein propose a random sampling-based analysis strategy termed ligand dilution analysis (LDA) for easily implemented aptamer-based receptor study. Receptor density on the cell surface can be calculated based on a regression model. By using a synergistic ligand dilution design, colocalization and differentiation of aptamer and monoclonal antibody (mAb) binding on a single receptor can be realized. Once this is accomplished, precise binding site and detailed aptamer-receptor binding mode can be further determined using molecular docking and molecular dynamics simulation. The ligand dilution strategy also sets the stage for an aptamer-based dynamics analysis of two- and three-dimensional motion and fluctuation of highly expressed receptors on the live cell membrane.
摘要：
细胞特异性适体提供了在单分子水平上研究膜受体的强大工具。适体的大多数靶受体在细胞表面高度表达，但由于分布密集和速度快，难以原位分析。因此,我们在此提出了一种基于随机抽样的分析策略，称为配体稀释分析（LDA），用于易于实施的基于适体的受体研究。可以基于回归模型计算细胞表面上的受体密度。通过使用协同配体稀释设计，可以实现适体和单克隆抗体（mAb）结合在单个受体上的共定位和分化。一旦完成，可以使用分子对接和分子动力学模拟进一步确定精确的结合位点和详细的适体-受体结合模式。配体稀释策略还为活细胞膜上高度表达的受体的二维和三维运动和波动的基于适体的动力学分析奠定了基础。
