The psiCHECK™-2 Vector is designed to provide quantitative and rapid optimization of RNA interference (RNAi). The vector enables monitoring of changes in expression of a target gene fused to a reporter gene. Renilla luciferase is used as the primary reporter gene, and the gene of interest is cloned into a multiple cloning region located downstream of the Renilla translational stop codon. Initiation of the RNAi process by synthetic siRNAs toward a gene of interest results in cleavage and subsequent degradation of the fusion mRNA. Measuring decreases in Renilla activity provides a convenient way of monitoring the RNAi effect.
In comparison with other fusion approaches (e.g., GFP or flag-tags), the Renilla luciferase approach offers more convenient and rapid quantitation with higher sensitivity. The psiCHECK™-2 Vector contains a second reporter gene, firefly luciferase, and is designed for endpoint lytic assays. Introduction of firefly luciferase in the psiCHECK™-2 Vector allows normalization of Renilla luciferase expression, achieving robust and reproducible results.