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 Helicases00:55

DNA Helicases

22.5K
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...
22.5K
The Replisome03:01

The Replisome

35.4K
DNA replication is carried out by a large complex of proteins that act in a coordinated matter to achieve high-fidelity DNA replication. Together this complex is known as the DNA replication machinery or the replisome.
The synthesis of the leading and lagging strands is a highly coordinated process. To explain this, the “Trombone model” was proposed by Bruce Alberts in 1980. The DNA loop formation starts when a primer is synthesized on the parent lagging strand. The loop grows with...
35.4K
Replication in Prokaryotes01:32

Replication in Prokaryotes

25.5K
DNA replication has three main steps: initiation, elongation, and termination. Replication in prokaryotes begins when initiator proteins bind to the single origin of replication (ori) on the cell's circular chromosome. Replication then proceeds around the entire circle of the chromosome in each direction from the two replication forks, resulting in two DNA molecules.
Many Proteins Work Together to Replicate the Chromosome
Replication is coordinated and carried out by a host of specialized...
25.5K
Replication in Eukaryotes01:29

Replication in Eukaryotes

14.9K
In eukaryotic cells, DNA replication is highly conserved and tightly regulated. Multiple linear chromosomes must be duplicated with high fidelity before cell division, so there are many proteins that fulfill specialized roles in the replication process. Replication occurs in three phases: initiation, elongation, and termination, and ends with two complete sets of chromosomes in the nucleus.
Many Proteins Orchestrate Replication at the Origin
Eukaryotic replication follows many of the same...
14.9K
Homologous Recombination02:31

Homologous Recombination

54.0K
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...
54.0K
Coordination of Gene Expression Processes in Bacteria01:29

Coordination of Gene Expression Processes in Bacteria

199
The DNA replication, transcription, and translation processes are intricately coupled in bacteria, allowing efficient gene expression and rapid protein synthesis. While this physical and functional coordination is advantageous, it introduces challenges that bacteria overcome through specific regulatory mechanisms.Coupling of Replication, Transcription, and TranslationThe coupling of replication, transcription, and translation is a hallmark of bacterial gene expression. As the replisome unwinds...
199

You might also read

Related Articles

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

Sort by
Same author

A modular framework for automated segmentation and analysis of AFM imaging of chromatin organization.

Nucleic acids research·2026
Same author

Distinct quaternary states, intermediates, and autoinhibition during loading of the DnaB-replicative helicase by the phage λP helicase loader.

Nucleic acids research·2025
Same author

DnaB and DciA: mechanisms of helicase loading and translocation on ssDNA.

Nucleic acids research·2025
Same author

Distinct Quaternary States, Intermediates, and Autoinhibition During Loading of the DnaB-Replicative Helicase by the Phage λP Helicase Loader.

bioRxiv : the preprint server for biology·2025
Same author

A disordered linker in the Polycomb protein Polyhomeotic tunes phase separation and oligomerization.

Molecular cell·2025
Same author

Mechanistic understanding of UvrA damage detection and lesion hand-off to UvrB in Nucleotide Excision Repair.

Nature communications·2025
Same journal

Metabolic control of RNA splicing by polyamines.

Trends in biochemical sciences·2026
Same journal

The role of glycan modifications in health and disease.

Trends in biochemical sciences·2026
Same journal

Strengthening the philosophical basis of graduate science education.

Trends in biochemical sciences·2026
Same journal

CycloPepper learns cyclization sites in therapeutic peptides.

Trends in biochemical sciences·2026
Same journal

Glycosphingolipids in cell identity: Biosynthesis, functions, and emerging tools.

Trends in biochemical sciences·2026
Same journal

Cap in hand: giant viruses, stolen translation, and a road to endosymbiosis?

Trends in biochemical sciences·2026
See all related articles

Related Experiment Video

Updated: Sep 28, 2025

Author Spotlight: Investigating the Motion Dynamics of the Eukaryotic Replisome Components at the Single-Molecule Level
10:11

Author Spotlight: Investigating the Motion Dynamics of the Eukaryotic Replisome Components at the Single-Molecule Level

Published on: July 26, 2024

1.2K

Convergent evolution in two bacterial replicative helicase loaders.

Jillian Chase1, James Berger2, David Jeruzalmi3

  • 1Department of Chemistry and Biochemistry, City College of New York, New York, NY 10031, USA; PhD Program in Biochemistry, The Graduate Center of the City University of New York, New York, NY 10016, USA.

Trends in Biochemical Sciences
|March 30, 2022
PubMed
Summary
This summary is machine-generated.

Bacterial DNA replication relies on loader proteins like E. coli DnaC and phage λ P to open DnaB helicases. These loaders, despite different sequences, share a common mechanism for helicase opening through molecular mimicry.

Keywords:
DNA replicationDnaBDnaC, λ Pconvergent evolutionhelicase loading

More Related Videos

Author Spotlight: Unraveling the Dynamics of Eukaryotic DNA Replication Through Single-Molecule Visualization
07:37

Author Spotlight: Unraveling the Dynamics of Eukaryotic DNA Replication Through Single-Molecule Visualization

Published on: September 27, 2024

1.8K
Strand-Specific Analysis of Proteins at Replicating DNA Strands by Enrichment and Sequencing of Protein-Associated Nascent DNA Method
08:53

Strand-Specific Analysis of Proteins at Replicating DNA Strands by Enrichment and Sequencing of Protein-Associated Nascent DNA Method

Published on: May 2, 2025

509

Related Experiment Videos

Last Updated: Sep 28, 2025

Author Spotlight: Investigating the Motion Dynamics of the Eukaryotic Replisome Components at the Single-Molecule Level
10:11

Author Spotlight: Investigating the Motion Dynamics of the Eukaryotic Replisome Components at the Single-Molecule Level

Published on: July 26, 2024

1.2K
Author Spotlight: Unraveling the Dynamics of Eukaryotic DNA Replication Through Single-Molecule Visualization
07:37

Author Spotlight: Unraveling the Dynamics of Eukaryotic DNA Replication Through Single-Molecule Visualization

Published on: September 27, 2024

1.8K
Strand-Specific Analysis of Proteins at Replicating DNA Strands by Enrichment and Sequencing of Protein-Associated Nascent DNA Method
08:53

Strand-Specific Analysis of Proteins at Replicating DNA Strands by Enrichment and Sequencing of Protein-Associated Nascent DNA Method

Published on: May 2, 2025

509

Area of Science:

  • Molecular biology
  • Bacterial DNA replication
  • Protein structure and function

Background:

  • Loader proteins are crucial for bacterial DNA replication.
  • They open ring-shaped DnaB-family helicases and chaperone single-stranded DNA.
  • Escherichia coli DnaC and bacteriophage λ P are key examples of these loaders.

Purpose of the Study:

  • To investigate the structural and mechanistic similarities between E. coli DnaC and bacteriophage λ P loaders.
  • To understand how these unrelated proteins achieve a common function in DNA replication.
  • To elucidate the mechanism of helicase ring opening.

Main Methods:

  • Comparative structural analysis of loader proteins and helicases.
  • Biophysical characterization of protein-DNA interactions.
  • Functional assays to assess helicase activity.

Main Results:

  • E. coli DnaC and λ P loaders share a similar architecture, with a globular domain and an extended lasso/grappling hook element.
  • Both loaders remodel the DnaB ring into nearly identical right-handed open conformations.
  • A single alpha helix is the conserved element binding to the same site on the helicase.

Conclusions:

  • DnaC and λ P evolved independently, converging on a common mechanism for helicase opening.
  • Molecular mimicry is the driving force behind this functional convergence.
  • This study reveals an example of convergent evolution in essential bacterial replication machinery.