Ligand-Induced Conformational Changes with Cation Ejection upon Binding to Human Telomeric DNA G-Quadruplexes

Autor: Keisuke Iida, Anton Granzhan, Adrien Marchand, Yue Ma, Valérie Gabelica, Marie-Paule Teulade-Fichou, Kazuo Nagasawa, Yamato Tsushima
Přispěvatelé: Acides Nucléiques : Régulations Naturelle et Artificielle (ARNA), Centre National de la Recherche Scientifique (CNRS)-Institut National de la Santé et de la Recherche Médicale (INSERM)-Institut de Chimie du CNRS (INC)-Université de Bordeaux (UB), Université de Bordeaux (UB)-Institut National de la Santé et de la Recherche Médicale (INSERM)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), Dissemin, Projet
Jazyk: angličtina
Rok vydání: 2015
Předmět:
Zdroj: Journal of the American Chemical Society
Journal of the American Chemical Society, American Chemical Society, 2015, 137 (2), pp.750-756. ⟨10.1021/ja5099403⟩
Journal of the American Chemical Society, 2015, 137 (2), pp.750-756. ⟨10.1021/ja5099403⟩
ISSN: 0002-7863
1520-5126
DOI: 10.1021/ja5099403⟩
Popis: International audience; The rational design of ligands targeting human telomeric DNA G‐q uadruplexes is a complex problem due to the structural polymorphism that these sequences can adopt in physiological conditions. Moreover, the ability of ligands to switch conformational equilibria between differ-ent G‐quadruplex structures is often overlooked in docking approaches. Here, we demonstrate that three of the most potent G-quadruplex ligands (360A, Phen-DC3 and pyridostatin) induce conformational changes of telomeric DNA G-quadruplexes to an antiparallel structure (as de-termined by circular dichroism) containing only one specifically coordinated K+ (as determined by electrospray mass spectrometry), and hence presumably only two consecutive G-quartets. Control ligands TrisQ, known to bind preferentially to hybrid than to antiparallel structures, and L2H2-6M(2)OTD, known not to disrupt the hybrid-1 structure, did not show such K+ re-moval. Instead, binding of the cyclic oxazole L2H2-6M(2)OTD was accompanied by the uptake of one additional K+. Also contrasting with telomeric G-quadruplexes, the parallel-stranded Pu24-myc G-quadruplex, to which Phen-DC3 is known to bind by end-stacking, did not under-go cation removal upon ligand binding. Our study therefore evidences that very affine ligands can induce conformational switching of the human telomeric G‐quadruplexes to an antiparallel structure, and that this conformational change is accompanied by removal of one inter-quartet cation.
Databáze: OpenAIRE