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

Homologous Recombination02:31

Homologous Recombination

61.9K
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...
61.9K
Conservative Site-specific Recombination and Phase Variation02:53

Conservative Site-specific Recombination and Phase Variation

6.5K
Because the DNA segments are cut and reorganized in a direction-specific manner, site-specific recombination has emerged as an efficient genetic engineering technique. Flippase and Cyclization recombinases or Flp and Cre, respectively, are two members of the tyrosine recombinase family derived from bacteriophages, that are used to mediate site-specific DNA insertions, deletions, and targeted expression of proteins in mammalian cell lines.
The recognition sites for Cre recombinase called LoxP...
6.5K
Crossing Over01:30

Crossing Over

5.9K
Crossing over is the exchange of genetic information between homologous chromosomes during prophase I of meiosis I. Genetic recombination gives rise to allelic diversity in the newly formed daughter cells. In humans, crossing over produces genetically distinct haploid egg and sperm cells that undergo fertilization to produce unique offspring. Before cell division starts, the germ cell’s chromosome(s) undergo duplication in the S phase of the cell cycle. As the cells enter prophase I,...
5.9K
Condensins02:15

Condensins

4.4K
Condensins are large protein complexes that use ATP to fuel the assembly of chromosomes during mitosis. They transform the tangled, shapeless mass of post-interphase DNA into individualized chromosomes by compacting, organizing, and segregating chromosomal DNA.
The plant and animal cells contain two types of condensin complexes—condensin I and condensin II. Both complexes have five subunits: two SMC (Structural Maintenance of Chromosomes) subunits, a kleisin subunit, and two HEAT-repeat...
4.4K
Restarting Stalled Replication Forks02:37

Restarting Stalled Replication Forks

6.2K
DNA replication is initiated at sites containing predefined DNA sequences known as origins of replication. DNA is unwound at these sites by the minichromosome maintenance (MCM) helicase and other factors such as Cdc45 and the associated GINS complex.The unwound single strands are protected by replication protein A (RPA) until DNA polymerase starts synthesizing DNA at the 5’ end of the strand in the same direction as the replication fork. To prevent the replication fork from falling apart,...
6.2K
Single-Strand DNA Binding Proteins01:03

Single-Strand DNA Binding Proteins

16.3K
For successful DNA replication, the unwinding of double-stranded DNA must be accompanied by stabilization and protection of the separated single strands of the DNA. This crucial task is performed by single-strand DNA-binding (SSB) proteins. They bind to the DNA in a sequence-independent manner, which means that the nitrogenous bases of the DNA need not be present in a specific order for binding of SSB proteins to it. The binding of SSB proteins straightens single-stranded DNA (ssDNA) and makes...
16.3K

You might also read

Related Articles

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

Sort by
Same author

An Accessible Python Framework for Real-Time Magnetic Tweezers Microscope Control and Image Processing.

bioRxiv : the preprint server for biology·2025
Same author

Quantitative Proteomics Reveals the Dynamic Regulation of the Tomato Proteome in Response to <i>Phytophthora infestans</i>.

International journal of molecular sciences·2021
Same author

Enhanced Photocatalytic Degradation of Antibiotic and Hydrogen Production by Iron Doped Cerium(IV) Oxide.

Journal of nanoscience and nanotechnology·2021
Same author

Modular Enzyme- and Light-Based Activation of Cyclopropene-Tetrazine Ligation.

Chembiochem : a European journal of chemical biology·2019

Related Experiment Video

Updated: Dec 21, 2025

Tools to Study the Role of Architectural Protein HMGB1 in the Processing of Helix Distorting, Site-specific DNA Interstrand Crosslinks
12:19

Tools to Study the Role of Architectural Protein HMGB1 in the Processing of Helix Distorting, Site-specific DNA Interstrand Crosslinks

Published on: November 10, 2016

8.6K

Polyamines stimulate RecA-mediated recombination by condensing duplex DNA and stabilizing intermediates.

Naciye Esma Tirtom1, Yang Hsu2, Hung-Wen Li1

  • 1Department of Chemistry, National Taiwan University, Taiwan. hwli@ntu.edu.tw.

Physical Chemistry Chemical Physics : PCCP
|May 21, 2020
PubMed
Summary
This summary is machine-generated.

Polyamines like spermine and spermidine condense DNA, enhancing RecA-mediated recombination. These molecules stimulate DNA duplex capture and stabilize key intermediates, promoting DNA repair and genetic diversity.

More Related Videos

Chemical Dimerization-Induced Protein Condensates on Telomeres
08:52

Chemical Dimerization-Induced Protein Condensates on Telomeres

Published on: April 12, 2021

3.5K
Preparation of Meiotic Chromosome Spreads from Mouse Oocytes for Assessment of Synapsis and Recombination
09:24

Preparation of Meiotic Chromosome Spreads from Mouse Oocytes for Assessment of Synapsis and Recombination

Published on: July 18, 2025

773

Related Experiment Videos

Last Updated: Dec 21, 2025

Tools to Study the Role of Architectural Protein HMGB1 in the Processing of Helix Distorting, Site-specific DNA Interstrand Crosslinks
12:19

Tools to Study the Role of Architectural Protein HMGB1 in the Processing of Helix Distorting, Site-specific DNA Interstrand Crosslinks

Published on: November 10, 2016

8.6K
Chemical Dimerization-Induced Protein Condensates on Telomeres
08:52

Chemical Dimerization-Induced Protein Condensates on Telomeres

Published on: April 12, 2021

3.5K
Preparation of Meiotic Chromosome Spreads from Mouse Oocytes for Assessment of Synapsis and Recombination
09:24

Preparation of Meiotic Chromosome Spreads from Mouse Oocytes for Assessment of Synapsis and Recombination

Published on: July 18, 2025

773

Area of Science:

  • Molecular Biology
  • Biochemistry
  • Genetics

Background:

  • Polyamines are vital cellular cations involved in gene expression and proliferation.
  • Polyamines are known to stimulate DNA recombination, but the mechanism remains unclear.
  • RecA protein is crucial for DNA repair and recombination.

Purpose of the Study:

  • To elucidate the molecular mechanism by which polyamines stimulate RecA-mediated DNA recombination.
  • To investigate the effect of polyamines on DNA structure and RecA filament interactions.

Main Methods:

  • Single-molecule tethered particle motion (TPM) experiments were employed.
  • The study analyzed the condensation of duplex DNA by polyamines (spermine and spermidine).
  • RecA filament activity and DNA capture were monitored in the presence of polyamines.

Main Results:

  • Spermine and spermidine exhibit differential efficiencies in condensing duplex DNA.
  • DNA condensation by polyamines is a stepwise and reversible process.
  • Polyamines significantly enhance RecA's duplex DNA capture activity and stabilize recombination intermediates, promoting recombination progression by approximately 20-fold.

Conclusions:

  • Polyamines facilitate RecA-mediated recombination by condensing DNA and stabilizing RecA-DNA complexes.
  • This study clarifies the molecular role of polyamines in promoting DNA repair and genetic recombination.