Jove
Visualize
Contact Us
JoVE
x logofacebook logolinkedin logoyoutube logo
ABOUT JoVE
OverviewLeadershipBlogJoVE Help Center
AUTHORS
Publishing ProcessEditorial BoardScope & PoliciesPeer ReviewFAQSubmit
LIBRARIANS
TestimonialsSubscriptionsAccessResourcesLibrary Advisory BoardFAQ
RESEARCH
JoVE JournalMethods CollectionsJoVE Encyclopedia of ExperimentsArchive
EDUCATION
JoVE CoreJoVE BusinessJoVE Science EducationJoVE Lab ManualFaculty Resource CenterFaculty Site
Terms & Conditions of Use
Privacy Policy
Policies

Related Concept Videos

DNA Topoisomerases02:02

DNA Topoisomerases

31.7K
Topoisomerases are enzymes that relax overwound DNA molecules during various cell processes, including DNA replication and transcription. These enzymes regulate positive and negative DNA supercoiling without changing the nucleotide sequence. DNA overwinding in a clockwise direction results in positively supercoiled DNA, whereas underwinding in a counterclockwise direction produces negatively supercoiled DNA.
Types and Mechanism of action
Topoisomerases are divided into two main types. ...
31.7K
Homologous Recombination02:31

Homologous Recombination

58.5K
The basic reaction of homologous recombination (HR) involves two chromatids that contain DNA sequences sharing a significant stretch of identity. One of these sequences uses a strand from another as a template to synthesize DNA in an enzyme-catalyzed reaction. The final product is a novel amalgamation of the two substrates. To ensure an accurate recombination of sequences, HR is restricted to the S and G2 phases of the cell cycle. At these stages, the DNA has been replicated already and the...
58.5K
Homologous Recombination02:31

Homologous Recombination

6.1K
6.1K
Gene Conversion02:08

Gene Conversion

9.2K
Other than maintaining genome stability via DNA repair, homologous recombination plays an important role in diversifying the genome. In fact, the recombination of sequences forms the molecular basis of genomic evolution. Random and non-random permutations of genomic sequences create a library of new amalgamated sequences. These newly formed genomes can determine the fitness and survival of cells. In bacteria, homologous and non-homologous types of recombination lead to the evolution of new...
9.2K
DNA Helicases00:55

DNA Helicases

19.1K
DNA unwinding helicase enzymes are a type of motor protein. Motor proteins can translocate along filaments or polymers using energy generated from ATP hydrolysis. Helicases are involved in all the important cellular processes where DNA unwinding is required, such as DNA replication, repair, recombination, and transcription. They are present in all living organisms, but vary in their structure, function, and mechanism of action. For example, in prokaryotes, DnaB helicase binds and translocates...
19.1K
Fixing Double-strand Breaks02:04

Fixing Double-strand Breaks

12.0K
The double-stranded structure of DNA has two major advantages. First, it serves as a safe repository of genetic information where one strand serves as the back-up in case the other strand is damaged. Second, the double-helical structure can be wrapped around proteins called histones to form nucleosomes, which can then be tightly wound to form chromosomes. This way, DNA chains up to 2 inches long can be contained within microscopic structures in a cell. A double-stranded break not only damages...
12.0K

You might also read

Related Articles

Articles linked to this work by shared authors, journal, and citation graph.

Sort by
Same author

Retraction Note: LncRNA TLR8-AS1 suppresses miR-34a maturation in hepatocellular carcinoma to suppress cell proliferation and migration.

Mammalian genome : official journal of the International Mammalian Genome Society·2023
Same author

Solution-processable polymers of intrinsic microporosity for gas-phase carbon dioxide photoreduction.

Nature communications·2023
Same author

Protein folding mechanism revealed by single-molecule force spectroscopy experiments.

Biophysics reports·2023
Same author

Rural-urban differences in characteristics, postoperative outcomes, and costs for patients undergoing knee arthroplasty: a national retrospective propensity score matched cohort study.

International journal of surgery (London, England)·2023
Same author

Comparing the accuracy of full-arch implant impressions using the conventional technique and digital scans with and without prefabricated landmarks in the mandible: An in vitro study.

Journal of dentistry·2023
Same author

Deep learning enables automatic adult age estimation based on CT reconstruction images of the costal cartilage.

European radiology·2023
Same journal

Carbonylative Aminative Suzuki-Miyaura Coupling: Pd-Catalyzed Synthesis of Amides from Vinyl/Aryl Halides and Boronic Acids.

Journal of the American Chemical Society·2026
Same journal

Divergent Asymmetric Synthesis of Glutinosasins A-E.

Journal of the American Chemical Society·2026
Same journal

Ultrastrong Polyketone Hot-Melt Adhesives Enabled by Ni-Catalyzed Carbonylative Polymerization.

Journal of the American Chemical Society·2026
Same journal

Programmable Anomalous Photovoltaics Enabled by Light-Electric Dual-Field Control.

Journal of the American Chemical Society·2026
Same journal

Biomimetic Redox-Mediated Proton Relay in Nanoreactors for Photocatalysis.

Journal of the American Chemical Society·2026
Same journal

The Sulfur Monoxide-Water Complex.

Journal of the American Chemical Society·2026
See all related articles

Related Experiment Video

Updated: Apr 21, 2026

Analyzing and Building Nucleic Acid Structures with 3DNA
16:24

Analyzing and Building Nucleic Acid Structures with 3DNA

Published on: April 26, 2013

20.3K

Interconversion between three overstretched DNA structures.

Xinghua Zhang1, Yuanyuan Qu, Hu Chen

  • 1BioSystems and Micromechanics, Singapore-MIT Alliance for Research and Technology , Singapore 138602, Singapore.

Journal of the American Chemical Society
|October 23, 2014
PubMed
Summary
This summary is machine-generated.

Researchers studied DNA overstretching transitions induced by salt concentration changes. They observed direct interconversions between DNA bubble, S-DNA, and peeled single-stranded DNA (ssDNA) structures under force, with peeled ssDNA to S-DNA conversion showing slow kinetics.

More Related Videos

Design and Synthesis of a Reconfigurable DNA Accordion Rack
07:44

Design and Synthesis of a Reconfigurable DNA Accordion Rack

Published on: August 15, 2018

6.7K
Stretching Short Sequences of DNA with Constant Force Axial Optical Tweezers
08:48

Stretching Short Sequences of DNA with Constant Force Axial Optical Tweezers

Published on: October 13, 2011

12.5K

Related Experiment Videos

Last Updated: Apr 21, 2026

Analyzing and Building Nucleic Acid Structures with 3DNA
16:24

Analyzing and Building Nucleic Acid Structures with 3DNA

Published on: April 26, 2013

20.3K
Design and Synthesis of a Reconfigurable DNA Accordion Rack
07:44

Design and Synthesis of a Reconfigurable DNA Accordion Rack

Published on: August 15, 2018

6.7K
Stretching Short Sequences of DNA with Constant Force Axial Optical Tweezers
08:48

Stretching Short Sequences of DNA with Constant Force Axial Optical Tweezers

Published on: October 13, 2011

12.5K

Area of Science:

  • Biophysics
  • Molecular Biology
  • Structural Biology

Background:

  • Double-stranded DNA (dsDNA) exhibits complex structural transitions under mechanical stress.
  • Torsion-unconstrained DNA can adopt overstretched conformations like peeled single-stranded DNA (ssDNA), DNA bubble, and S-DNA at high forces.

Purpose of the Study:

  • To investigate the interconversion dynamics between different overstretched DNA structures.
  • To understand the influence of salt concentration on these structural transitions at constant force.

Main Methods:

  • Utilized atomic force microscopy or similar single-molecule force spectroscopy techniques.
  • Applied controlled forces (above 70 pN) and varied NaCl concentrations.
  • Observed stepwise extension changes indicative of structural interconversions.

Main Results:

  • Demonstrated direct interconversions between S-DNA and DNA bubble structures in end-closed DNA constructs.
  • Showcased direct interconversions between S-DNA and peeled ssDNA in end-opened DNA constructs.
  • Identified ultraslow kinetics for the peeled ssDNA to S-DNA conversion, attributed to secondary hairpin formation.

Conclusions:

  • Salt concentration plays a crucial role in mediating interconversions between overstretched DNA structures.
  • The observed kinetics provide insights into the molecular mechanisms governing DNA structural plasticity under force.
  • Findings enhance understanding of DNA behavior in non-physiological conditions and its structural versatility.