In Vivo Processing Assay Based on a Dual-Luciferase Reporter System to Evaluate DROSHA Enzymatic Activity

Luciferase reporter assays are widely used to study promoter activity, transcription factors, intracellular signaling, protein interactions (Jia et al., PloS One 6:e26414), miRNA processing (Allegra and Mertens, Biochem Biophys Res Commun 406:501–505), and target recognition (Jin et al., Methods Mol Biol 936:117–127). Here we describe the use of a dual-luciferase reporter system to evaluate the enzymatic activity of a key enzyme involved in RNA maturation—DROSHA. This dual system is a simple and fast method for the quantification of the DROSHA processing activity in live cells.