The miRNA Sensor reporter gene vector is mainly used to detect changes in the activity of target miRNAs in cells, such as the effect of competitive endogenous RNA (ceRNA) on miRNA activity. Based on the pmiR-RB-Report™ vector backbone, RiboBio’s miRNA Sensor reporter gene vector clones the binding sequence of target miRNAs to the downstream of Renilla luciferase genes (hRluc), and the target miRNA can regulate the renilla luciferase through the binding sequence, thus making the Renilla luciferase gene a reporter gene and the firefly luciferase gene (hLuc) an internal reference gene. By doing so, the changes in the activity of miRNAs in cells can be identified through the relative change of Renilla luciferase activity. For instance, by regulating the high expression of ceRNAs in miRNAs, miRNAs can be binded to ceRNAs, and the miRNA activity will decrease, while the activity of Renilla luciferase will climb up.