Development of ribonucleopeptide-based fluorescent sensors for biologically active amines based on the stepwise molding strategy

General strategy for the development of fluorescent biosensors as a tracer of 'key' molecule in the cellular system would provide important breakthroughs for ubiquitous applications in the field of diagnosis and pharmacology in addition to our understanding of cellular events. The sophisticated design of fluorescent biosensors based on the organic synthesis is one of the promising approaches, but this type of biosensors frequently fail to maintain their performance in the cellular environment despite of laborious protocols. Another procedure for simultaneous preparation of a wide variety of fluorescent biosensors for the optical monitoring of a target molecule represents an especially attractive alternative. In our continuous efforts, we have recently developed a conceptually new strategy for coincidental production of fluorescent biosensors with diverse functions based on a framework of ribonucleopeptide (RNP). RNP-based fluorescent sensors were fabricated with a combination of in vitro selection method and a successive modification of the peptide of RNP with a fluorophore. Each RNP composed of a ligand-binding RNA subunit and a fluorophore-tagged peptide motif facilitated the fluorometric detection of biologically active amines with a unique binding affinity and an inherent fluorescent signal.