UP-REGULATION OF LUCIFERASE GENE-EXPRESSION WITH ANTISENSE OLIGONUCLEOTIDES - IMPLICATIONS AND APPLICATIONS IN FUNCTIONAL ASSAY DEVELOPMENTS

HeLa Tet-Off cells were transfected transiently as well as stably with a recombinant plasmid (pLuc/705) carrying the luciferase gene interru pted by a mutated human beta-globin intron 2 (IVS2-705). The mutation in the intron causes aberrant splicing of luciferase pre-mRNA, prevent ing translation of luciferase. However, treatment of the cells with a 2'-O-methyl-oligoribonucleotide targeted to the aberrant splice sites induces correct splicing, restoring luciferase activity, The effects a re sequence-specific, depend on the concentration of the oligonucleoti de, and can be modulated by the pretreatment of the cell line, Luc/705 , with tetracycline. Thus, the cell line provides, among others, a nov el functional assay system superior to other procedures that are based on protein down-regulation. In particular, the system would be ideal in assessing the cellular delivery efficiency of antisense oligonucleo tides.