title: Verification of specific G-quadruplex structure by using a novel cyanine dye supramolecular assembly: II. The binding characterization with specific intramolecular G-quadruplex and the recognizing mechanism.
abstract: The supramolecular assembly of a novel cyanine dye, 3,3'-di(3-sulfopropyl)-4,5,4',5'-dibenzo-9-ethyl-thiacarbocyanine triethylammonium salt (ETC) was designed to verify specific intramolecular G-quadruplexes from duplex and single-strand DNAs. Spectral results have shown that ETC presented two major distinct signatures with specific intramolecular G-quadruplexes in vitro: (i) dramatic changes in the absorption spectra (including disappearance of absorption peak around 660 nm and appearance of independent new peak around 584 nm); (ii) approximately 70 times enhancement of fluorescence signal at 600 nm. Furthermore, based on (1)H-nuclear magnetic resonance and circular dichroism results, the preferring binding of ETC to specific intramolecular G-quadruplexes probably result from end-stacking, and the loop structure nearby also plays an important role.
authors.affiliation: Institute of Chemistry, Chinese Academy of Sciences, Beijing, 100190, People's Republic of China.
authors.forename: Qianfan
authors.initials: Q
authors.lastname: Yang
authors.forename: Junfeng
authors.initials: J
authors.lastname: Xiang
authors.forename: Shu
authors.initials: S
authors.lastname: Yang
authors.forename: Qian
authors.initials: Q
authors.lastname: Li
authors.forename: Qiuju
authors.initials: Q
authors.lastname: Zhou
authors.forename: Aijiao
authors.initials: A
authors.lastname: Guan
authors.forename: Xiufeng
authors.initials: X
authors.lastname: Zhang
authors.forename: Hong
authors.initials: H
authors.lastname: Zhang
authors.forename: Yalin
authors.initials: Y
authors.lastname: Tang
authors.forename: Guangzhi
authors.initials: G
authors.lastname: Xu
mesh_terms: D002232:Carbocyanines / Q000737:chemistry*; D004247:DNA / Q000737:chemistry*; D004277:DNA, Single-Stranded / Q000737:chemistry; D005456:Fluorescent Dyes / Q000737:chemistry*; D054856:G-Quadruplexes; D008958:Models, Molecular; D019906:Nuclear Magnetic Resonance, Biomolecular; D013050:Spectrometry, Fluorescence; D013053:Spectrophotometry
chemical_list: C548165:3,3'-di(3-sulfopropyl)-4,5,4',5'-dibenzo-9-ethyl-thiacarbocyanine; D002232:Carbocyanines; D004277:DNA, Single-Stranded; D005456:Fluorescent Dyes; D004247:DNA