Intron Retained Bioluminescence Reporter for Real-Time Imaging of Pre-mRNA Splicing in Living Subjects

Pre-mRNA splicing in the information exchange from DNA to protein is a critical step in all eukaryotes. However, there is currently a lack of noninvasive approaches for monitoring mRNA splicing events in cells. In this study, we presented a genetically encoded bioluminescence reporter, Rluc-intron, for noninvasive real-time monitoring the pre-mRNA splicing process in living cells and animals. It was designed by inserting a renilla luciferase (Rluc) gene into an intron sequence manipulated by RNA splicing modulator. We demonstrated that the splicing reporter Rluc-intron could provide real-time and quantitative information on the splicing activity responded to extracellular stimuli in living cells. In addition, Rluc-intron reporter is able to successfully quantify and image the pre-mRNA splicing in living mice in a noninvasive and longitudinal manner. This bioluminescence reporter provides the advantageous properties of systematic discovery of splicing modulators, which give the advances in pharmacogenomics and would produce new approach in the therapy of human diseases caused by splicing disorder.