The effect of osmolytes and small molecule on Quadruplex-WC duplex equilibrium: a fluorescence resonance energy transfer study.

ABSTRACT: The structural competition between the G-quadruplex and Watson-Crick duplex has been implicated for the repetitive DNA sequences, but the factors influencing this competitive equilibrium in the natural and pharmacological context need to be elucidated. Using a 21mer 5'-Fluorescein-d[(G3TTA)3G3]-TAMRA-3' as a model system, extensive fluorescence resonance energy transfer analysis was carried out to investigate sensitivity of this equilibrium to osmotic stress and quadruplex selective small molecule. The binding affinities and kinetics involved in the hybridization of quadruplex to its complementary strand in the absence and presence of different concentrations of osmolytes (ethylene glycol and glycerol) and a quadruplex selective ligand (cationic porphyrin-TMPyP4) were determined. The prese

SUBMITTER: Kumar N 

PROVIDER: S-EPMC1301592 | biostudies-literature | 2005

REPOSITORIES: biostudies-literature