INDEPENDENT REGULATION OF 2 SEPARATE GENE ACTIVITIES IN A CONTINUOUS HUMAN CELL-LINE

Tetracycline- and ecdysone-responsive systems have recently been devel oped for regulated gene expression in eukaryotic cells. Using nucleola r-targeted luciferase and P-galactosidase as reporter proteins we demo nstrate that both systems can function simultaneously and independentl y in a continuous human cell line. Both gene activities could be regul ated over a broad range and at the single cell level by the concentrat ions of tetracycline and muristerone A, respectively, in the culture m edium. The strategy described here will allow to investigate the funct ion and interaction of two separate gene activities in a well-defined and reproducible cellular context.