HAIRPIN, DUMBBELL, AND SINGLE-STRANDED PHOSPHODIESTER OLIGONUCLEOTIDES EXHIBIT IDENTICAL UPTAKE IN T-LYMPHOCYTE CELL-LINES

The cellular binding, uptake, and intracellular distribution of struct ured double-stranded phosphodiester oligonucleotides (decoys) have bee n examined in T lymphocytes using fluorescein-labeled molecules, Intra cellular localization of hairpin and dumbbell decoys was similar to th at of single-stranded oligonucleotides. At short incubation times, oli gonucleotides were localized only in cytoplasmic vesicles, whereas at longer times, they were also found in the nucleus, Cellular uptake was dependent on temperature, time, and extracellular concentration, Olig onucleotide efflux was similar for all types of molecules and was very rapid (t(1/2)=10-15 minutes). These results imply that phosphodiester double-stranded oligonucleotides can enter cellular compartments of i nterest for their potential biologic function and, thus, provide a pot ential tool to control gene transcription.