title: End-to-end stacking and liquid crystal condensation of 6 to 20 base pair DNA duplexes.
abstract: Short complementary B-form DNA oligomers, 6 to 20 base pairs in length, are found to exhibit nematic and columnar liquid crystal phases, even though such duplexes lack the shape anisotropy required for liquid crystal ordering. Structural study shows that these phases are produced by the end-to-end adhesion and consequent stacking of the duplex oligomers into polydisperse anisotropic rod-shaped aggregates, which can order into liquid crystals. Upon cooling mixed solutions of short DNA oligomers, in which only a small fraction of the DNA present is complementary, the duplex-forming oligomers phase-separate into liquid crystal droplets, leaving the unpaired single strands in isotropic solution. In a chemical environment where oligomer ligation is possible, such ordering and condensation would provide an autocatalytic link whereby complementarity promotes the extended polymerization of complementary oligomers.
authors.affiliation: Department of Physics and Liquid Crystal Materials Research Center, University of Colorado, Boulder, CO 80309-0390, USA.
authors.forename: Michi
authors.initials: M
authors.lastname: Nakata
authors.forename: Giuliano
authors.initials: G
authors.lastname: Zanchetta
authors.forename: Brandon D
authors.initials: BD
authors.lastname: Chapman
authors.forename: Christopher D
authors.initials: CD
authors.lastname: Jones
authors.forename: Julie O
authors.initials: JO
authors.lastname: Cross
authors.forename: Ronald
authors.initials: R
authors.lastname: Pindak
authors.forename: Tommaso
authors.initials: T
authors.lastname: Bellini
authors.forename: Noel A
authors.initials: NA
authors.lastname: Clark
mesh_terms: D016880:Anisotropy; D020029:Base Pairing; D003460:Crystallization; D004247:DNA / Q000737:chemistry*; D009690:Nucleic Acid Conformation; D009838:Oligodeoxyribonucleotides / Q000737:chemistry; D044367:Phase Transition; D013696:Temperature; D013816:Thermodynamics; D014961:X-Ray Diffraction
chemical_list: D009838:Oligodeoxyribonucleotides; D004247:DNA