A nucleic acid probe labeled with desmethyl thiazole orange: a new type of hybridization-sensitive fluorescent oligonucleotide for live-cell RNA imaging

Abstract

A new fluorescent nucleotide with desmethyl thiazole orange dyes, D′₅₀₅, has been developed for expansion of the function of fluorescent probes for live-cell RNA imaging. The nucleoside unit of D′₅₀₅ for DNA autosynthesis was soluble in organic solvents, which made the preparation of nucleoside units and the reactions in the cycles of DNA synthesis more efficient. The dyes of D′₅₀₅-containing oligodeoxynucleotide were protonated below pH 7 and the oligodeoxynucleotide exhibited hybridization-sensitive fluorescence emission through the control of excitonic interactions of the dyes of D′₅₀₅. The simplified procedure and effective hybridization-sensitive fluorescence emission produced multicolored hybridization-sensitive fluorescent probes, which were useful for live-cell RNA imaging. The acceptor-bleaching method gave us information on RNA in a specific cell among many living cells.