I have used the human CMV promoter previously for my mouse cell line with low performance. Will a different promoter increase shRNA functionality?

Poor performance may be due to low transduction efficiency or suboptimal promoter activity. Optimization of transduction conditions is essential to successful gene silencing as well as understanding promoter activity. Promoter activity varies in different cell lines and cell types, and we highly recommend using the SMARTchoice shRNA Promoter Selection Plate to determine the most active promoter in your cells of interest. For example, the mouse CMV promoter in NIH/3T3 cells results in significantly increased promoter activity and greater gene silencing compared to the same shRNA expressed from the human CMV promoter in this cell line.