Homogeneous detection of viral nucleic acid via selective recognition proximity ligation and signal amplification with T7 transcription and CRISPR/Cas12a system

The synthetic biology has employed the synthetic gene networks through engineering to construct various functions in biological systems. However, the use of gene circuits to create sensors for detecting low-abundance targets has been limited due to the lack of signal amplification strategies beyond direct output of detection signals. To address this issue, we introduce a novel method utilizing Selective Recognition Proximity Ligation and signal amplification with T7 Transcription and CRISPR/Cas12a system (SRPL-TraCs), which permits the incorporation of cell-free gene circuits with signal amplification and enables the construction of high-order cascade signal amplification strategy to detect biomarkers in homogeneous systems. Specifically, the SRPLTraCs utilizes selective recognition proximity ligation with high-fidelity T4 DNA ligase and generates a unique crRNA via T7 transcription, along with target-activated Cas12a/crRNA system to achieve excellent specificity for HIV-1 DNA. With this straightforward synthetic biology-based method, the proposed SRPL-TraCs has the po-tential to detect numerous other interesting targets beyond the nucleic acids.

Automated summary

In this study, a novel method called SRPL-TraCs is introduced, which combines selective recognition proximity ligation and signal amplification strategies to construct a high-order cascade signal amplification strategy for detecting biomarkers. This method shows excellent specificity and potential, not only for nucleic acids, but also for other interesting targets.