have studied the sequence dependent binding of 2-amino-1,8-naphthyridine derivative 1 to a single guanine bulge. The free energy changes for the binding to a guanine bulge with different sequence contexts (5'X_Y3'/3'X'GY'5') were determined by a curve fitting of the thermal denaturation profile of DNA in the presence and absence of 1. The data showed that (i) the binding of 1 to a guanine bulge is stronger
Photoswitchable DNA-binding ligands should be useful for controlling diverse biological functions involving DNA and reversible assembly of DNA-based nanostructures. In work directed towards the development of photoswitchableligands with various sequence specificities, we have elaborated an efficient synthesis of photoswitchableunsymmetricalligands possessing pairs of different base recognition elements
Molecular glue for DNA is a small synthetic ligand that adheres two single-stranded DNAs to produce a double-stranded DNA. We previously devised a photoswitchable molecular glue (PMG) that uses external light stimuli to reversibly control DNA hybridization. To optimize the structure of PMG, we synthesized a series of PMGs and evaluated the effect of changing the methylene linker length on the binding
An inhibitor contains naphthyridine dimer, a naphthyridine-azaquinolone hybrid, a trinaphthyridine-azaquinolone hybrid, or a trinaphthyridine-azaquinolone hybrid derivative. In order to inhibit binding of 100 nM of RRE to 100 nM of Rev protein, for example, an inhibitor containing naphthyridine dimer is used at a molarity of 1.2 μM to 12 μM, an inhibitor containing the naphthyridine-azaquinolone hybrid is used at a molarity of 2 μM to 20 μM, or an inhibitor containing the trinaphthyridine-azaquinolone hybrid derivative is used at a molarity of 200 nM to 2 μM. This makes it possible to effectively inhibit binding of RRE to Rev protein.
Naphthyridine dimer (ND) specially binds to guanine-guanine (G-G) mismatch in duplex DNA. In order to improve the thermal and alkaline stability and binding ability of the ligand, we have examined structural modification of the linker. A new ligand (NNC) possessing 2-amino-1,8-naphthyridines and a carbamate linker is much more thermally stable than ND. The half-life of NNC is 2.5 times longer than that of ND at 80degreesC. NNC is also much more stable than ND under alkaline conditions. In addition, NNC binds to G-G mismatch more strongly than ND. The improved stability and the binding of NNC to the G-G mismatch would be suitable for the practical use of NNC-immobilized sensor. (C) 2004 Elsevier Ltd. All rights reserved.