title: Interactions of daidzin with intramolecular G-quadruplex.
abstract: The potential interaction of daidzin, an ingredient of soy isoflavones, with human telomeric antiparallel G-quadruplex dAG(3)(T(2)AG(3))(3) was studied using ESI-MS, PAGE, CD and molecular simulation. Experimental studies indicated that daidzin molecules interacted with dAG(3)(T(2)AG(3))(3) and formed DNA-daidzin complex with the stoichiometric ratio of 1:1 and 1:2. The transition temperature of the G-quadruplex increased at higher ratio of daidzin to DNA. Under molecular crowding conditions the interactions between daidzin and the G-quadruplex become much stronger. Combining computational simulation and experimental results, it is demonstrated that the dAG(3)(T(2)AG(3))(3)/daidzin complex with a stoichiometric ratio of 1:1 is stabilized through the pi-pi conjugacy interactions and hydrogen bondings between daidzin and the bases of G-quadruplex. This work provides guidance not only on exploring the molecular anti-cancer mechanism of dietary isoflavones, but also searching small natural products as promising anticancer candidates that can inhibit telomerase activity.
authors.affiliation: Department of Chemical Technology, School of Chemical Engineering and Technology, Tianjin University, Tianjin 300072, China.
authors.forename: Wei
authors.initials: W
authors.lastname: Li
authors.forename: Ming
authors.initials: M
authors.lastname: Zhang
authors.forename: Jin-li
authors.initials: JL
authors.lastname: Zhang
authors.forename: Hui-qing
authors.initials: HQ
authors.lastname: Li
authors.forename: Xiao-chen
authors.initials: XC
authors.lastname: Zhang
authors.forename: Qian
authors.initials: Q
authors.lastname: Sun
authors.forename: Chun-mei
authors.initials: CM
authors.lastname: Qiu
mesh_terms: D002942:Circular Dichroism; D004791:Enzyme Inhibitors / Q000737:chemistry / Q000378:metabolism; D006147:Guanine / Q000378:metabolism*; D006801:Humans; D006860:Hydrogen Bonding; D007529:Isoflavones / Q000737:chemistry / Q000378:metabolism*; D046911:Macromolecular Substances; D008958:Models, Molecular; D015394:Molecular Structure; D009690:Nucleic Acid Conformation; D009692:Nucleic Acid Heteroduplexes; D012091:Repetitive Sequences, Nucleic Acid
chemical_list: D004791:Enzyme Inhibitors; D007529:Isoflavones; D046911:Macromolecular Substances; D009692:Nucleic Acid Heteroduplexes; C013908:daidzin; D006147:Guanine