双化合物诱导细胞谱系示踪系统（DISC）的建立及其在骨损伤修复中的应用

骨损伤在临床上比较常见，其愈合时间长，甚至出现骨不连，治疗难度高，寻找参与骨损伤修复的细胞谱系有望揭示其分子细胞学机制，为探索促进骨损伤愈合的治疗方法提供依据。目前研究骨损伤修复的细胞谱系主要用特异启动子结合标记物、荧光蛋白等谱系示踪方法，这些方法存在特异性差、假阳性高等缺点。基于DNA条形码的谱系示踪与单细胞测序联用技术，弥补了荧光谱系示踪的不足，为解析骨损伤修复的分子细胞机制提供了有力工具。现用于小鼠的Polylox等DNA条形码技术存在本底背景高等不足，需要改进。本项目针对这些不足将建立一种基于DNA条形码的双化合物诱导的细胞谱系示踪系统（DISC），可更加特异，准确地示踪细胞谱系。进一步将DISC系统应用于颅骨再生修复研究，解析FGFR2+细胞在在修复中的作用与机制。本项目实施将为开发促进骨损伤修复的策略提供新思路，也为其它组织器官的发育、疾病、再生机制研究提供有力工具。

Bone injury is common in clinical practice, with long healing time and even nonunion, which is difficult to treat. Looking for cell lineages involved in bone injury repair is expected to reveal its molecular cytological mechanism and provide basis for exploring therapeutic strategy to promote bone injury healing. At present, the cell lineage of bone injury repair is mainly studied by lineage tracing that combining specific promoter with fluorescent proteins, which have the shortcomings of poor specificity and high false positives. Lineage tracing based on DNA barcoding, combined with single cell RNA sequencing technology, provides a powerful tool for analyzing the molecular and cellular mechanism of bone injury repair. DNA barcoding techniques such as Polylox used in mice need to be improved due to their high background etc. To address these deficiencies, this project will establish a “Dual-compound induced system for cell lineage tracing (DISC)” that based on DNA barcoding, which can trace cell lineage more specifically and accurately. The DISC system was further applied to study of skull injury and repair, and the role and mechanism of FGFR2+ cells in the repair also were analyzed. The implementation of this project will provide new ideas for the development of strategies to promote the repair of bone injury, and provide powerful tools for the research on the development, disease and regeneration mechanism of other tissues and organs.