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G-quadruplex DNA bound by a synthetic ligand is highly dynamic.

ABSTRACT: Using single molecule fluorescence resonance energy transfer, we investigated the interaction between a quadruplex-binding ligand and the human telomeric G-quadruplex. The binding of quinolinecarboxamide macrocycle to telomeric DNA was essentially irreversible and selectively induced and favored one quadruplex conformation. The ligand-quadruplex complex displayed intramolecular dynamics including quadruplex folding and unfolding in the absence of ligand association and dissociation. We report that the G-quadruplex can be stabilized without preventing the intrinsic intramolecular dynamics of telomeric DNA.

SUBMITTER: Jena PV

PROVIDER: S-EPMC2737377 | biostudies-literature | 2009 Sep

REPOSITORIES: biostudies-literature

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G-quadruplex DNA bound by a synthetic ligand is highly dynamic.

Jena Prakrit V PV Shirude Pravin S PS Okumus Burak B Laxmi-Reddy Katta K Godde Frédéric F Huc Ivan I Balasubramanian Shankar S Ha Taekjip T

Journal of the American Chemical Society 20090901 35

Using single molecule fluorescence resonance energy transfer, we investigated the interaction between a quadruplex-binding ligand and the human telomeric G-quadruplex. The binding of quinolinecarboxamide macrocycle to telomeric DNA was essentially irreversible and selectively induced and favored one quadruplex conformation. The ligand-quadruplex complex displayed intramolecular dynamics including quadruplex folding and unfolding in the absence of ligand association and dissociation. We report th ...[more]

PMID: 19685880

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