Probing DNA and RNA single molecules with a double optical tweezer.
A double-tweezer setup is used to induce mechanical stress in systems of molecular biology. A double strand of DNA is first stretched and the data is compared to precedent experiments to check the experimental setup. Then a short foldable fragment of RNA is probed; the typical unfolding/refolding hysteresis behaviour of this kind of construction is shown and followed by a study of its elasticity and a comparison to a worm-like chain model. Eventually, we describe the unfolding of a larger RNA structure, which unfolds by multiple steps. We show that this unfolding is not reversible and that it presents numerous unfolding pathways.
Mangeol
P
P
Laboratoire de Nanobiophysique, UMR CNRS 7083, ESPCI, 10 rue Vauquelin, 75231, Paris Cedex 05, France.
Côte
D
D
Bizebard
T
T
Legrand
O
O
Bockelmann
U
U
D004247:DNA / Q000737:chemistry* / Q000648:ultrastructure; D004926:Escherichia coli / Q000235:genetics; D018625:Microscopy, Atomic Force / Q000295:instrumentation / Q000379:methods; D008958:Models, Molecular; D008961:Models, Structural; D009691:Nucleic Acid Denaturation; D012313:RNA / Q000737:chemistry* / Q000648:ultrastructure; D012329:RNA, Bacterial / Q000737:chemistry; D012335:RNA, Ribosomal / Q000737:chemistry
D012329:RNA, Bacterial; D012335:RNA, Ribosomal; D012313:RNA; D004247:DNA