title: Organelle-mimicking liposome dissociates G-quadruplexes and facilitates transcription.
abstract: Important biological reactions involving nucleic acids occur near the surface of membranes such as the nuclear membrane (NM) and rough endoplasmic reticulum (ER); however, the interactions between biomembranes and nucleic acids are poorly understood. We report here that transcription was facilitated in solution with liposomes, which mimic a biomembrane surface, relative to the reaction in a homogeneous aqueous solution when the template was able to form a G-quadruplex. The G-quadruplex is known to be an inhibitor of transcription, but the stability of the G-quadruplex was decreased at the liposome surface because of unfavourable enthalpy. The destabilization of the G-quadruplex was greater at the surface of NM- and ER-mimicking liposomes than at the surfaces of liposomes designed to mimic other organelles. Thermodynamic analyses revealed that the G-rich oligonucleotides adopted an extended structure at the liposome surface, whereas in solution the compact G-quadruplex was formed. Our data suggest that changes in structure and stability of nucleic acids regulate biological reactions at membrane surfaces.
authors.affiliation: Frontier Institute for Biomolecular Engineering Research (FIBER), Konan University, 7-1-20 Minatojima-minamimachi, Chuo-ku, Kobe 650-0047, Japan.
authors.forename: Smritimoy
authors.initials: S
authors.lastname: Pramanik
authors.affiliation: Frontier Institute for Biomolecular Engineering Research (FIBER), Konan University, 7-1-20 Minatojima-minamimachi, Chuo-ku, Kobe 650-0047, Japan.
authors.forename: Hisae
authors.initials: H
authors.lastname: Tateishi-Karimata
authors.affiliation: Frontier Institute for Biomolecular Engineering Research (FIBER), Konan University, 7-1-20 Minatojima-minamimachi, Chuo-ku, Kobe 650-0047, Japan Graduate School of Frontiers of Innovative Research in Science and Technology (FIRST), Konan University, 7-1-20 Minatojima-minamimachi, Chuo-ku, Kobe 650-0047, Japan sugimoto@konan-u.ac.jp.
authors.forename: Naoki
authors.initials: N
authors.lastname: Sugimoto
mesh_terms: D004247:DNA / Q000737:chemistry; D018870:Endoplasmic Reticulum, Rough / Q000737:chemistry; D054856:G-Quadruplexes; D007425:Intracellular Membranes / Q000737:chemistry; D008081:Liposomes / Q000737:chemistry*; D051336:Mitochondrial Membranes / Q000737:chemistry; D008958:Models, Molecular; D009685:Nuclear Envelope / Q000737:chemistry; D012313:RNA / Q000737:chemistry; D013816:Thermodynamics; D014158:Transcription, Genetic
chemical_list: D008081:Liposomes; D012313:RNA; D004247:DNA