title: Light-up Hoechst-DNA aptamer pair: generation of an aptamer-selective fluorophore from a conventional DNA-staining dye.
abstract: We have designed a strategy to generate a light-up fluorophore-aptamer pair based on a down-modification of a conventional DNA-staining dye to suppress its affinity to the original dsDNA targets, followed by reselection of aptamers that would bind to the modified dye. Following this line, we prepared a micropolarity-sensitive Hoechst derivative possessing two tBu groups with low affinity to the usual AT-rich dsDNA targets. DNA aptamers selected in vitro from a random pool worked as triggers to enhance the fluorescence of an otherwise nonfluorescent Hoechst derivative, and the shortened 25-mer sequence showed remarkable enhancement (light-up). The 25-mer sequence was split into binary aptamer probes, thus enabling us to detect a target nucleic acid sequence with a single-nucleotide resolution by use of unmodified DNA as a probe.
authors.affiliation: Department of Synthetic Chemistry and Biological Chemistry, Graduate School of Engineering, Kyoto University, Katsura, Nishikyo-ku, Kyoto 615-8510, Japan. ssando@sbchem.kyoto-u.ac.jp
authors.forename: Shinsuke
authors.initials: S
authors.lastname: Sando
authors.forename: Atsushi
authors.initials: A
authors.lastname: Narita
authors.forename: Yasuhiro
authors.initials: Y
authors.lastname: Aoyama
mesh_terms: D000255:Adenosine Triphosphate / Q000378:metabolism; D052157:Aptamers, Nucleotide / Q000737:chemistry* / Q000378:metabolism; D020029:Base Pairing; D001483:Base Sequence; D015374:Biosensing Techniques / Q000379:methods*; D015342:DNA Probes; D005456:Fluorescent Dyes / Q000737:chemistry*; D009690:Nucleic Acid Conformation; D013050:Spectrometry, Fluorescence