title: Two structurally analogous ruthenium complexes as naked-eye and reversible molecular "light switch" for G-quadruplex DNA.
abstract: A pair of symmetrical furyl based ruthenium(II) complexes ([Ru(phen)2dpq-df](2+) (1) and [Ru(bpy)2dpq-df](2+) (2) (phen=1,10-phenanthroline, bpy=2,2'-bipyridine, dpq-df=dipyrido (3,2-a:2',3'-c) quinoxaline-difuran) have been prepared and characterized. The binding properties of both complexes toward G-quadruplex DNA have been investigated by fluorescence spectroscopy, UV-Vis spectroscopy, circular dichroism (CD), fluorescence resonance energy transfer (FRET) melting assays and molecular docking studies. The experimental results indicated that both Ru-complexes exhibited a remarkable "light switch" effect in the presence of hybrid G-quadruplex DNA. Interestingly, the "light switch" can be repeated off and on through the successive addition of Cu(2+) ions and EDTA, and all these behaviors can be observed even by the naked eyes. Moreover, FRET melting assay revealed that both complexes could be potential stabilizers for G-quadruplex architectures. The computational studies not only confirmed that the two complex molecules bound to one G-quadruplex DNA molecule, but also explained the "light switch" effect.
authors: Department of Chemistry, Tongji University, Shanghai 200092, PR China.
authors: Xiao-Hui
authors: XH
authors: Lu
authors: Department of Chemistry, Tongji University, Shanghai 200092, PR China. Electronic address: shishuo@tongji.edu.cn.
authors: Shuo
authors: S
authors: Shi
authors: Department of Chemistry, Tongji University, Shanghai 200092, PR China.
authors: Jun-Liang
authors: JL
authors: Yao
authors: Department of Chemistry, Tongji University, Shanghai 200092, PR China.
authors: Xing
authors: X
authors: Gao
authors: Department of Chemistry, Tongji University, Shanghai 200092, PR China.
authors: Hai-Liang
authors: HL
authors: Huang
authors: Department of Chemistry, Tongji University, Shanghai 200092, PR China. Electronic address: tmyao@tongji.edu.cn.
authors: Tian-Ming
authors: TM
authors: Yao
mesh_terms: D002942:Circular Dichroism; D031541:Fluorescence Resonance Energy Transfer; D054856:G-Quadruplexes; D062105:Molecular Docking Simulation; D066244:Proton Magnetic Resonance Spectroscopy; D017975:Ruthenium Compounds / Q000737:chemistry*; D019032:Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization
chemical_list: D017975:Ruthenium Compounds
keywords: G-quadruplex DNA; Light switch; Molecular docking; Naked-eye and reversible; Ruthenium complexes