title: Molecular force spectroscopy with a DNA origami-based nanoscopic force clamp.
abstract: Forces in biological systems are typically investigated at the single-molecule level with atomic force microscopy or optical and magnetic tweezers, but these techniques suffer from limited data throughput and their requirement for a physical connection to the macroscopic world. We introduce a self-assembled nanoscopic force clamp built from DNA that operates autonomously and allows massive parallelization. Single-stranded DNA sections of an origami structure acted as entropic springs and exerted controlled tension in the low piconewton range on a molecular system, whose conformational transitions were monitored by single-molecule Förster resonance energy transfer. We used the conformer switching of a Holliday junction as a benchmark and studied the TATA-binding protein-induced bending of a DNA duplex under tension. The observed suppression of bending above 10 piconewtons provides further evidence of mechanosensitivity in gene regulation.
authors.affiliation: Faculty of Physics and Center for NanoScience, Ludwig-Maximilians-Universität, Geschwister-Scholl-Platz 1, 80539 München, Germany.
authors.forename: Philipp C
authors.initials: PC
authors.lastname: Nickels
authors.affiliation: Institut für Physikalische und Theoretische Chemie, Braunschweig Integrated Centre of Systems Biology, and Laboratory for Emerging Nanometrology, Technische Universität Braunschweig, Rebenring 56, 38106 Braunschweig, Germany.
authors.forename: Bettina
authors.initials: B
authors.lastname: Wünsch
authors.affiliation: Institut für Physikalische und Theoretische Chemie, Braunschweig Integrated Centre of Systems Biology, and Laboratory for Emerging Nanometrology, Technische Universität Braunschweig, Rebenring 56, 38106 Braunschweig, Germany.
authors.forename: Phil
authors.initials: P
authors.lastname: Holzmeister
authors.affiliation: Faculty of Physics and Center for NanoScience, Ludwig-Maximilians-Universität, Geschwister-Scholl-Platz 1, 80539 München, Germany.
authors.forename: Wooli
authors.initials: W
authors.lastname: Bae
authors.affiliation: Faculty of Physics and Center for NanoScience, Ludwig-Maximilians-Universität, Geschwister-Scholl-Platz 1, 80539 München, Germany.
authors.forename: Luisa M
authors.initials: LM
authors.lastname: Kneer
authors.affiliation: Institut für Physikalische und Theoretische Chemie, Braunschweig Integrated Centre of Systems Biology, and Laboratory for Emerging Nanometrology, Technische Universität Braunschweig, Rebenring 56, 38106 Braunschweig, Germany.
authors.forename: Dina
authors.initials: D
authors.lastname: Grohmann
authors.affiliation: Institut für Physikalische und Theoretische Chemie, Braunschweig Integrated Centre of Systems Biology, and Laboratory for Emerging Nanometrology, Technische Universität Braunschweig, Rebenring 56, 38106 Braunschweig, Germany. p.tinnefeld@tu-braunschweig.de tim.liedl@physik.lmu.de.
authors.forename: Philip
authors.initials: P
authors.lastname: Tinnefeld
authors.affiliation: Faculty of Physics and Center for NanoScience, Ludwig-Maximilians-Universität, Geschwister-Scholl-Platz 1, 80539 München, Germany. p.tinnefeld@tu-braunschweig.de tim.liedl@physik.lmu.de.
authors.forename: Tim
authors.initials: T
authors.lastname: Liedl
mesh_terms: D045566:DNA, Cruciform / Q000737:chemistry / Q000648:ultrastructure*; D004277:DNA, Single-Stranded / Q000737:chemistry / Q000648:ultrastructure*; D031541:Fluorescence Resonance Energy Transfer / Q000379:methods*; D005786:Gene Expression Regulation; D036103:Nanotechnology / Q000379:methods; D011401:Promoter Regions, Genetic; D011485:Protein Binding; D000072760:Single Molecule Imaging / Q000379:methods*; D013314:Stress, Mechanical; D035181:TATA-Box Binding Protein / Q000737:chemistry / Q000648:ultrastructure
chemical_list: D045566:DNA, Cruciform; D004277:DNA, Single-Stranded; D035181:TATA-Box Binding Protein