Visualization of nucleic acids with synthetic exciton- controlled fluorescent oligonucleotide probes

Engineered probes to adapt new photochemical properties upon recognition of target nucleic acids offer powerful tools to DNA and RNA visualization technologies. Herein, we describe a rapid and effective visualization method of nucleic acids in both fixed and living cells with hybridization-sensitive fluorescent oligonucleotide probes. These probes are efficiently quenched in an aqueous environment due to the homodimeric, excitonic interactions between fluorophores but become highly fluorescent upon hybridization to DNA or RNA with complementary sequences. The fast hybridization kinetics and quick fluorescence activation of the new probes allow applications to simplify the conventional fl uorescent in situ hybridization protocols and reduce the amount of time to process the samples. Furthermore, hybridizationsensitive fluorescence emission of the probes allows monitoring dynamic behaviors of RNA in living cells.