title: Communication: Asymmetrical cation movements through G-quadruplex DNA.
abstract: G-quadruplex is a specific DNA structure stabilized by cations dwelling between adjacent G-quartets. The cation which dwelling in the coordination sites can move to the bulk solution through two terminals of G-quadruplex in an asymmetrical manner. In this study, we used molecular dynamics simulations and adaptive biasing force method to investigate the influence of glycosidic bond orientations of guanosines on the moving of cations through the G-quartet. We found that syn glycosidic bond orientation penalizes the escaping of K(+) ions, which results in the asymmetrical cation movements through the two terminals of G-quadruplexes. Nonetheless, the syn orientations have slight influence on the energy barrier for Na(+) ions penetrating the terminal G-quartets because of its relatively smaller radius. This study contributes to the understanding of the asymmetrical cation displacement in G-quadruplex systems.
authors.affiliation: CAS Key Laboratory of Soft Matter Chemistry, Department of Polymer Science and Engineering, University of Science and Technology of China, Hefei, Anhui 230026, People's Republic of China.
authors.forename: Hong
authors.initials: H
authors.lastname: Zhu
authors.affiliation: CAS Key Laboratory of Soft Matter Chemistry, Department of Polymer Science and Engineering, University of Science and Technology of China, Hefei, Anhui 230026, People's Republic of China.
authors.forename: Shiyan
authors.initials: S
authors.lastname: Xiao
authors.affiliation: CAS Key Laboratory of Soft Matter Chemistry, Department of Polymer Science and Engineering, University of Science and Technology of China, Hefei, Anhui 230026, People's Republic of China.
authors.forename: Lei
authors.initials: L
authors.lastname: Wang
authors.affiliation: CAS Key Laboratory of Soft Matter Chemistry, Department of Polymer Science and Engineering, University of Science and Technology of China, Hefei, Anhui 230026, People's Republic of China.
authors.forename: Haojun
authors.initials: H
authors.lastname: Liang
mesh_terms: D002412:Cations / Q000737:chemistry*; D004247:DNA / Q000737:chemistry*; D054856:G-Quadruplexes; D006151:Guanosine / Q000737:chemistry; D006860:Hydrogen Bonding; D056004:Molecular Dynamics Simulation; D011188:Potassium / Q000737:chemistry; D012964:Sodium / Q000737:chemistry; D012996:Solutions
chemical_list: D002412:Cations; D012996:Solutions; D006151:Guanosine; D004247:DNA; D012964:Sodium; D011188:Potassium