Fig. 4. Transfection of CNR cells with the LE-TFEB expression vector. A, TFEB expression in the G418-resistant CNR cells, as revealed by nonradioactive in situ hybridization (a). Note that the G418-resistant CNR cells obtained after LE transfection were not labeled (b). B, activity of Mi and TFEB proteins encoded by the LE vectors. Quail RPE cells were transfected with 1 µg of pMT2.2, a plasmid that contains a 2.2-kb fragment 5' of the transcriptional start site of the mouse tyrosinase gene cloned upstream the luciferase coding sequence, and 5 µg of either the LE-TFEB or LE-mi expression plasmid. The vector control used was the empty LE DNA. Cells were solubilized, and luciferase activities were assayed.