利用等离子激元纳米天线在高浓度单核苷酸精度下实时追踪单个转录和复制过程

DNA复制和转录过程属于细胞中最为重要的分子生物学过程。在单核苷酸精度下实时追踪转录和复制过程对于揭示其微观机制至关重要。本项目中，我们拟开发一种由DNA介导两个金球组装而成的“哑铃形”等离子激元纳米天线，并通过理论和实验手段，来优化、表征和精细调控金球间隙内光场。进而利用其作为一个高灵敏的单分子检测平台，配合多通道单分子荧光检测技术，最终实现高浓度单核苷酸精度下对单分子转录和复制过程的实时追踪。项目的研究成果将为未来以极高精度揭示转录和复制过程的动力学机制和调控机理打下坚实基础，同时也将为开发新的单分子测序技术铺平道路。

DNA replication and transcription are the two of the most important molecular processes in cell. It is essential to be able to track transcription and replication processes at the single-molecule level with single-nucleotide resolution in order to disclose the mechanism behind them. In this proposal, we plan to make a dumbbell-shape plasmonic nano-antenna by using a short segment of DNA to link with two gold nano-particles. Using both theoretical and experimental methods, we will investigate how parameters like particle size, gap distance, illumination configurations, etc. will tune the optical field inside the nano-gap of the antenna. Further, we plan to use this nano-antenna as a highly sensitive platform for single-molecule detection which will allow us to track transcription and replication processes at single-molecule level with single-nucleotide resolution and also under high (i.e. physiologically-relevant) nucleotide concentration. The results will not only lay a solid foundation for the study of the kinetics and regulation mechanism of transcription and replication with ultra-high precision, but also pave the way for developing a new single-molecule sequencing technique in the future.