title: Self-assembly of double-stranded DNA molecules at nanomolar concentrations.
abstract: Some proteins have the property of self-assembly, known to be an important mechanism in constructing supramolecular architectures for cellular functions. However, as yet, the ability of double-stranded (ds) DNA molecules to self-assemble has not been established. Here we report that dsDNA molecules also have a property of self-assembly in aqueous solutions containing physiological concentrations of Mg2+. We show that DNA molecules preferentially interact with molecules with an identical sequence and length even in a solution composed of heterogeneous DNA species. Curved DNA and DNA with an unusual conformation and property also exhibit this phenomenon, indicating that it is not specific to usual B-form DNA. Atomic force microscopy (AFM) directly reveals the assembled DNA molecules formed at concentrations of 10 nM but rarely at 1 nM. The self-assembly is concentration-dependent. We suggest that the attractive force causing DNA self-assembly may function in biological processes such as folding of repetitive DNA, recombination between homologous sequences, and synapsis in meiosis.
authors.affiliation: Department of Biology, Faculty of Science and Engineering, Konan University, 8-9-1 Okamoto, Higashinada-ku, Kobe 658-8501, Japan.
authors.forename: Shotaro
authors.initials: S
authors.lastname: Inoue
authors.forename: Shigeru
authors.initials: S
authors.lastname: Sugiyama
authors.forename: Andrew A
authors.initials: AA
authors.lastname: Travers
authors.forename: Takashi
authors.initials: T
authors.lastname: Ohyama
mesh_terms: D001483:Base Sequence; D004247:DNA / Q000737:chemistry* / Q000378:metabolism; D017931:DNA Primers / Q000737:chemistry / Q000378:metabolism; D007700:Kinetics; D008969:Molecular Sequence Data; D009690:Nucleic Acid Conformation
chemical_list: D017931:DNA Primers; D004247:DNA