Trans-splicing reaction efficiency. Real-time quantitative RT-PCR was performed to assess the efficiency of the trans-splicing reaction in a pool of cells. T268M-stable cells were transfected with ribozyme or inactive ribozyme. A mix control was included in which ribozyme-treated HEK-293 cells and nontransfected T268M-stable cells were combined prior to RNA isolation. Error bars indicate SEM.