Abstract
The three-dimensional structure of DNA is highly susceptible to changes by mechanical and biochemical cues in vivo and in vitro. In particular, large increases in base pair spacing compared to regular B-DNA are effected by mechanical (over)stretching and by intercalation of compounds that are widely used in biophysical/chemical assays and drug treatments. We present single-molecule experiments and a three-state statistical mechanical model that provide a quantitative understanding of the interplay between B-DNA, overstretched DNA and intercalated DNA. The predictions of this model include a hitherto unconfirmed hyperstretched state, twice the length of B-DNA. Our force-fluorescence experiments confirm this hyperstretched state and reveal its sequence dependence. These results pin down the physical principles that govern DNA mechanics under the influence of tension and biochemical reactions. A predictive understanding of the possibilities and limitations of DNA extension can guide refined exploitation of DNA in, e.g., programmable soft materials and DNA origami applications.
Original language | English |
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Article number | 2197 |
Journal | Nature Communications |
Volume | 8 |
Issue number | 1 |
DOIs | |
Publication status | Published - 19 Dec 2017 |
Funding
We acknowledge support by the Netherlands Organization for Scientific Research (NWO) through project no. 712.012.007 (P.v.d.S.), the Human Frontier Science Program via a Research Grant (E.J.G.P.) and NWO VIDI (I.H.), VICI (G.J.L.W.) as well as an ERC Starting Grant (G.J.L.W.). We thank G. A. King for discussions.
Funders | Funder number |
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Netherlands Organization for Scientific Research | |
VICI | |
Human Frontier Science Program | |
European Research Council | |
Nederlandse Organisatie voor Wetenschappelijk Onderzoek | 712.012.007 |