利用框架诱导自组装策略原位解析蛋白质膜上识别与结合的动力学过程

蛋白质在膜上的识别与结合过程在生命体系中发挥着十分重要的作用。如G蛋白偶联受体、表皮生长因子受体等蛋白是通过细胞膜上一系列精细、复杂的识别与结合过程来实现其生化活性，从而调控细胞内的各种代谢过程。宏观生化表征与微观静态结构分析等当前主要的蛋白研究手段虽然能够获取蛋白的静态信息，但无法原位解析蛋白质在膜上的识别与结合的动态过程，因此发展适用于膜蛋白的原位动态过程研究的新技术是当前蛋白研究的重要问题。本项目拟运用框架诱导自组装策略，以基于三维DNA框架的纳米磷脂生物膜为模板，通过疏水相互作用将膜蛋白重组于该可控膜结构中，并利用DNA框架的特异性识别将不同膜蛋白可控地引入同一膜环境，最终通过冷冻电镜与生物化学方法，实现膜蛋白识别与结合过程的原位观察。通过本项目的实施，我们将化学自组装方法应用于理解生命过程中重要的基本分子机制，同时也为原位地研究膜蛋白的作用机制提出一种全新的方法。

Protein recognition and binding play key roles in biological processes, e.g. GPCR and ErBB family proteins, which regulate the subsequent metabolism in cell through protein recognition and oligomerization/binding to realize the biological functions. Currently, the most important tools to investigate this process are still static structure and biochemical analysis, however, it is still challenging to characterize the protein recognition and binding in situ. This project will apply Frame Guided Assembly strategy to prepare lipid nano-membrane with 3D DNA structures as the frame and then reconstitute different membrane proteins into the controllable membranes through hydrophobic interactions. Due to the controllability and addressability of the DNA frame, the membrane which reconstitute different proteins could be guided close to fuse with each, and therefore, the subsequent protein recognition and binding process could be in situ characterized by both Cryo-EM and other biological tools. Through our project, we will apply chemical assembly strategy to investigate and reveal the possible molecular mechanism of life and provide a novel and universal tool to investigate the membrane protein interactions in situ.