title: Real-time observation of G-quadruplex dynamics using single-molecule FRET microscopy.
abstract: The potential importance of G-quadruplex structures was implied by the recent findings that the human POT1 disrupts G-quadruplex and stimulates the telomerase activity. A solid understanding of the range of conformations that can be adopted by guanine-rich sequences can potentially shed much light on the molecular mechanisms underlying certain human diseases related to telomeres. Furthermore, structure-based design of chemotherapeutic drugs for cancer might be realized by addressing different types of G-quadruplex structures. Using the unique capabilities of single-molecule spectroscopy, we have recently reported on the intricate dynamic structural properties of a minimal form of human telomeric DNA. Here, we present the detailed step-by-step methods for the real-time observation of G-rich DNA sequences by means of single-molecule FRET microscopy and provide the protocols for vesicle encapsulation and surface immobilization assays. Such assays provide a firm basis for future studies aimed at elucidating the interaction between telomeric DNA and telomere-associated proteins as well as the synthetic therapeutic agents that specifically stabilize certain G-quadruplex topologies.
authors.affiliation: Department of Physics, University of Illinois at Urbana Champaign, Urbana, IL, USA.
authors.forename: Burak
authors.initials: B
authors.lastname: Okumus
authors.forename: Taekjip
authors.initials: T
authors.lastname: Ha
mesh_terms: D004247:DNA / Q000737:chemistry* / Q000648:ultrastructure*; D031541:Fluorescence Resonance Energy Transfer / Q000379:methods*; D054856:G-Quadruplexes; D006147:Guanine / Q000737:chemistry*; D006801:Humans; D008081:Liposomes; D016615:Telomere / Q000737:chemistry* / Q000648:ultrastructure*
chemical_list: D008081:Liposomes; D006147:Guanine; D004247:DNA