Display Settings:

Format

Send to:

Choose Destination
Biophys J. 2004 Nov;87(5):3388-96. Epub 2004 Aug 31.

Dynamics of the DNA duplex formation studied by single molecule force measurements.

Author information

  • 1Laboratoire Pierre Aigrain, Ecole Normale Supérieure, Paris, France. ulrich@lpa.ens.fr

Abstract

DNA is partly denatured in vitro by applying a force that mechanically separates the two strands of the double helix. Sudden reduction of the imposed displacement triggers spontaneous reannealing of the molecule. The corresponding force signals are measured by optical trapping interferometry for backward steps of various amplitudes and base sequence intervals. The measured signals frequently show plateaus of varying duration at discrete values that are dependent on the base sequence. Additional measurements are performed with proteins bound to the double helix. When the opening fork encounters such a protein during mechanical unzipping, force increases until the protein is ejected. This ejection induces fast release of tension and fast unzipping. Comparing our different measurements, we find that both DNA unzipping and the relaxation of tension in DNA are faster than the formation of the double helix.

PMID:
15339815
[PubMed - indexed for MEDLINE]
PMCID:
PMC1304805
Free PMC Article

Images from this publication.See all images (11)Free text

FIGURE 1
FIGURE 2
FIGURE 3
FIGURE 4
FIGURE 5
FIGURE 6
FIGURE 7
FIGURE 8
FIGURE 9
FIGURE 10
FIGURE 11
PubMed Commons home

PubMed Commons

0 comments
How to join PubMed Commons

    Supplemental Content

    Full text links

    Icon for Elsevier Science Icon for PubMed Central
    Loading ...
    Write to the Help Desk