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

Cryo-electron Microscopy01:28

Cryo-electron Microscopy

3.4K
Conventional electron microscopy (EM) involves dehydration, fixation, and staining of biological samples, which distorts the native state of biological molecules and results in several artifacts. Also, the high-energy electron beam damages the sample and makes it difficult to obtain high-resolution images. These issues can be addressed using cryo-EM, which uses frozen samples and gentler electron beams. The technique was developed by Jacques Dubochet, Joachim Frank, and Richard Henderson, for...
3.4K
DNA Helicases00:55

DNA Helicases

21.6K
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...
21.6K

You might also read

Related Articles

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

Sort by
Same author

The molecular architecture of tunneling nanotubes.

bioRxiv : the preprint server for biology·2026
Same author

Structure of the human HIRA histone chaperone with a nucleosome suggests a stepwise nucleosome assembly mechanism.

bioRxiv : the preprint server for biology·2026
Same author

Reduced DNA repair capacity by lymphocytes in response to PM2.5 and wood smoke exposure predicts risk for lung cancer and COPD.

Environmental research·2026
Same author

Molecular basis of nick ligation in the nucleosome by DNA Ligase IIIα.

bioRxiv : the preprint server for biology·2026
Same author

Global genomic diversity of the selfing nematode <i>Caenorhabditis tropicalis</i> correlates with geography.

bioRxiv : the preprint server for biology·2026
Same author

N-Glycans modulate tilting of HIV-1 envelope glycoprotein.

Nature communications·2026

Related Experiment Video

Updated: Jul 28, 2025

Visualization of DNA Compaction in Cyanobacteria by High-voltage Cryo-electron Tomography
09:47

Visualization of DNA Compaction in Cyanobacteria by High-voltage Cryo-electron Tomography

Published on: July 17, 2018

9.2K

Cryo-EM visualization of DNA-PKcs structural intermediates in NHEJ.

Siyu Chen1,2, Alex Vogt1,2, Linda Lee3

  • 1Department of Molecular Biosciences, Northwestern University, Evanston, IL, USA.

Science Advances
|May 31, 2023
PubMed
Summary

DNA double-strand breaks (DSBs) are repaired by nonhomologous end joining (NHEJ). This study reveals how DNA-PKcs regulates NHEJ complex transitions via conformational changes, exposing DNA breaks for repair.

More Related Videos

Preparation of Nucleosome Core Particles Complexed with DNA Repair Factors for Cryo-Electron Microscopy Structural Determination
07:59

Preparation of Nucleosome Core Particles Complexed with DNA Repair Factors for Cryo-Electron Microscopy Structural Determination

Published on: August 17, 2022

1.9K
Do's and Don'ts of Cryo-electron Microscopy: A Primer on Sample Preparation and High Quality Data Collection for Macromolecular 3D Reconstruction
09:25

Do's and Don'ts of Cryo-electron Microscopy: A Primer on Sample Preparation and High Quality Data Collection for Macromolecular 3D Reconstruction

Published on: January 9, 2015

46.3K

Related Experiment Videos

Last Updated: Jul 28, 2025

Visualization of DNA Compaction in Cyanobacteria by High-voltage Cryo-electron Tomography
09:47

Visualization of DNA Compaction in Cyanobacteria by High-voltage Cryo-electron Tomography

Published on: July 17, 2018

9.2K
Preparation of Nucleosome Core Particles Complexed with DNA Repair Factors for Cryo-Electron Microscopy Structural Determination
07:59

Preparation of Nucleosome Core Particles Complexed with DNA Repair Factors for Cryo-Electron Microscopy Structural Determination

Published on: August 17, 2022

1.9K
Do's and Don'ts of Cryo-electron Microscopy: A Primer on Sample Preparation and High Quality Data Collection for Macromolecular 3D Reconstruction
09:25

Do's and Don'ts of Cryo-electron Microscopy: A Primer on Sample Preparation and High Quality Data Collection for Macromolecular 3D Reconstruction

Published on: January 9, 2015

46.3K

Area of Science:

  • Molecular Biology
  • Biochemistry
  • Structural Biology

Background:

  • DNA double-strand breaks (DSBs) are highly cytotoxic DNA lesions.
  • The nonhomologous end joining (NHEJ) pathway repairs DSBs through a series of regulated protein complex transitions.
  • Core NHEJ factors initially form a long-range (LR) synaptic complex that transitions to a short-range state for DNA end alignment.

Purpose of the Study:

  • To visualize and characterize key transition states of NHEJ complexes.
  • To elucidate the role and conformational dynamics of DNA-PKcs during NHEJ.
  • To reveal the regulatory cycle of DNA-PKcs in DSB repair.

Main Methods:

  • Single-particle cryo-electron microscopy (cryo-EM).
  • Structural analysis of multiple NHEJ complexes.
  • Investigation of DNA-PKcs conformations and autophosphorylation effects.

Main Results:

  • Three additional NHEJ transition states were visualized by cryo-EM.
  • DNA-PKcs adopts distinct dimeric conformations throughout the NHEJ process.
  • Autophosphorylation of DNA-PKcs induces conformational changes in the LR complex, promoting DNA break exposure and dissociation.

Conclusions:

  • DNA-PKcs undergoes significant conformational changes during NHEJ.
  • These dynamic changes are crucial for regulating DNA break exposure and processing.
  • A comprehensive model for the DNA-PKcs regulatory cycle in NHEJ is proposed.