title: Orderly microaggregates of G-/C-rich oligonucleotides associated with spermine.
abstract: Spermine-induced orderly assembling properties of G-/C-rich oligonucleotides are investigated in dilute and crowding conditions. The first time we report that the parallel G-quadruplexes is preferential to condense into anisotropic microaggregates in the presence of spermine, whereas the hybrid-type and the antiparallel G-quadruplexes have no significant interactions with spermine; and spermine can induce the condensation of i-motif C-rich oligonucleotides other than the random coiled C-rich strands. Moreover, the condensation of C-rich oligonucleotides can be reversibly regulated by pH and temperature. G-/C-rich oligonucleotides exhibit the cholesteric liquid crystalline phase at low strand concentration in the presence of spermine under crowding conditions. The results illuminate that the parallel G-quadruplex and i-motifs are probably necessity conformations for G-/C-rich oligonucleotides that involved in the regulation of chromosome organization in living cells.
authors.affiliation: Key Laboratory for Green Chemical Technology MOE, Tianjin University, Tianjin 300072, People's Republic of China.
authors.forename: Yan
authors.initials: Y
authors.lastname: Fu
authors.forename: Xian
authors.initials: X
authors.lastname: Wang
authors.forename: Jinli
authors.initials: J
authors.lastname: Zhang
authors.forename: Ying
authors.initials: Y
authors.lastname: Xiao
authors.forename: Wei
authors.initials: W
authors.lastname: Li
authors.forename: Jingkang
authors.initials: J
authors.lastname: Wang
mesh_terms: D001482:Base Composition; D054856:G-Quadruplexes; D006863:Hydrogen-Ion Concentration; D009690:Nucleic Acid Conformation / Q000187:drug effects; D009841:Oligonucleotides / Q000737:chemistry*; D044367:Phase Transition; D011487:Protein Conformation; D013096:Spermine / Q000494:pharmacology*; D013696:Temperature
chemical_list: D009841:Oligonucleotides; D013096:Spermine