Monitoring promoter activity by RNA editing based reporter

Abstract

Traditional methods monitoring the promoter activity require the insertion of reporter protein (e.g. fluorescent protein) downstream of a targeted promoter. These approaches suffer from low sensitivity and potential interference to endogenous transcripts especially when the targeted transcript is a noncoding RNA. Here, we develop a mechanistically different reporter system to monitor promoter activity based on ribozyme processed ADAR engaging RNA directed editing (REDDIT). We show that REDDIT can be used to monitor the promoter activity of protein coding, long noncoding RNA, and microRNA (miRNA) genes. Furthermore, REDDIT reporter can also be adapted to use bioluminescence imaging to monitor the promoter activity, which is more suitable for in vivo live imaging. Finally, the reporter sensitivity may be further increased by the circularization of ADAR recruiting RNA. REDDIT provides a powerful platform that is promising in a variety of applications such as monitoring the promoter activity, cell lineage tracing, and processing and manipulating genetic information for synthetic biology applications.