Synthetic DNA Transducers Integrate DNA Repair to CRISPR Signal Transduction

CRISPR-based molecular diagnostics have revolutionized nucleic acid detection, yet the integration of upstream enzyme activity into programmable CRISPR output remains largely unexplored. Here, we present a synthetic transduction platform that directly couples endogenous DNA repair activity with CRISPR-Cas12a activation. By linking base excision repair (BER) events to the structural switching of a programmable DNA transducer, we convert the activity of DNA glycosylases, such as uracil DNA glycosylase (UDG) and human 8-oxoguanine glycosylase (hOGG1), into a robust fluorescence signal via Cas12a-mediated collateral (trans-) cleavage. This one-step assay allows rapid and sensitive lysate-based detection of repair activity with high specificity. In addition, it can also be easily adapted to achieve rapid throughput screening of small molecule inhibitors. The rational modular design supports the adaptation to various glycosylase activities, establishing a general framework for transducing DNA repair activity into programmable CRISPR output. Beyond bioanalytical applications, this approach paves the way for the development of synthetic gene circuits that respond to DNA repair activity and CRISPR-based drug screening platforms.