title: Biomechanics of DNA structures visualized by 4D electron microscopy.
abstract: We present a technique for in situ visualization of the biomechanics of DNA structural networks using 4D electron microscopy. Vibrational oscillations of the DNA structure are excited mechanically through a short burst of substrate vibrations triggered by a laser pulse. Subsequently, the motion is probed with electron pulses to observe the impulse response of the specimen in space and time. From the frequency and amplitude of the observed oscillations, we determine the normal modes and eigenfrequencies of the structures involved. Moreover, by selective "nano-cutting" at a given point in the network, it was possible to obtain Young's modulus, and hence the stiffness, of the DNA filament at that position. This experimental approach enables nanoscale mechanics studies of macromolecules and should find applications in other domains of biological networks such as origamis.
authors: Physical Biology Center for Ultrafast Science and Technology, Arthur Amos Noyes Laboratory of Chemical Physics, California Institute of Technology, Pasadena, CA 91125, USA.
authors: Ulrich J
authors: UJ
authors: Lorenz
authors: Ahmed H
authors: AH
authors: Zewail
mesh_terms: D001696:Biomechanical Phenomena; D004247:DNA / Q000737:chemistry*; D008854:Microscopy, Electron / Q000379:methods*; D009690:Nucleic Acid Conformation
chemical_list: D004247:DNA
references: Curr Opin Struct Biol. 2000 Jun;10(3):279-85
references: 10851197
references: Nature. 2012 Nov 1;491(7422):42-3
references: 23128220
references: Nature. 2003 Jan 23;421(6921):423-7
references: 12540915
references: Phys Rev B Condens Matter Mater Phys. 2011 Jun 15;83(24):
references: 26207085
references: Science. 2010 Apr 9;328(5975):187-93
references: 20378810
references: Nano Lett. 2008 Nov;8(11):3557-62
references: 19006405
references: Nano Lett. 2011 May 11;11(5):2183-91
references: 21513332
references: Science. 2010 Jun 25;328(5986):1668-73
references: 20576886
references: Prog Biophys Mol Biol. 2000;74(1-2):37-61
references: 11106806
references: Biopolymers. 1987 Oct;26(10):1637-65
references: 3663850
references: Nat Mater. 2007 Nov;6(11):841-50
references: 17972939
references: Phys Rev E Stat Nonlin Soft Matter Phys. 2008 Aug;78(2 Pt 1):021907
references: 18850865
references: J Am Chem Soc. 2012 Jun 6;134(22):9146-9
references: 22591381
references: Science. 1996 Feb 9;271(5250):795-9
references: 8628994
references: Nat Nanotechnol. 2011 Nov 06;6(12):763-72
references: 22056726
references: Phys Rev Lett. 2010 Mar 5;104(9):095501
references: 20366992
references: Nat Nanotechnol. 2007 May;2(5):275-84
references: 18654284
references: Nature. 2003 Sep 11;425(6954):145
references: 12968169
references: Annu Rev Phys Chem. 2009;60:217-39
references: 19012538
references: Phys Rev Lett. 2004 Apr 2;92(13):134302
references: 15089617
references: Nano Lett. 2009 Feb;9(2):875-81
references: 19133756
references: Science. 2008 Sep 26;321(5897):1795-9
references: 18818351
references: Nature. 1999 Apr 1;398(6726):407-10
references: 10201370