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

CRISPR/Cas9 Genome Editing01:28

CRISPR/Cas9 Genome Editing

1.5K
The CRISPR-Cas system serves as a bacterial defense mechanism against invading genetic elements such as viruses and plasmids, forming the foundation for its adaptation as a powerful genome-editing tool. Originally discovered in prokaryotes, this system has been repurposed to revolutionize genetic engineering across a wide range of organisms, including plants, animals, and humans. The core component, Cas9, is an endonuclease derived from Streptococcus pyogenes, capable of introducing...
1.5K
CRISPR and crRNAs02:53

CRISPR and crRNAs

18.6K
Bacteria and archaea are susceptible to viral infections just like eukaryotes; therefore, they have developed a unique adaptive immune system to protect themselves. Clustered regularly interspaced short palindromic repeats and CRISPR-associated proteins (CRISPR-Cas) are present in more than 45% of known bacteria and 90% of known archaea.
The CRISPR-Cas system stores a copy of foreign DNA in the host genome and uses it to identify the foreign DNA upon reinfection. CRISPR-Cas has three different...
18.6K
CRISPR01:59

CRISPR

57.3K
Genome editing technologies allow scientists to modify an organism’s DNA via the addition, removal, or rearrangement of genetic material at specific genomic locations. These types of techniques could potentially be used to cure genetic disorders such as hemophilia and sickle cell anemia. One popular and widely used DNA-editing research tool that could lead to safe and effective cures for genetic disorders is the CRISPR-Cas9 system. CRISPR-Cas9 stands for Clustered Regularly Interspaced...
57.3K
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

You might also read

Related Articles

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

Sort by
Same author

The Extract of <i>Salvia miltiorrhiza</i> 'Hongdan' Attenuates Inflammation in LPS-Activated BV2 Microglia via ERK1/2, JNK, and p38 MAPK Signaling Inhibition.

Pharmaceuticals (Basel, Switzerland)·2026
Same author

ATP is dispensable for E. coli DNA replication and eukaryotic helicase activity.

Nature communications·2026
Same author

DepoCatalog: mapping diversity of 129 recombinantly produced Klebsiella phage depolymerases.

Nature communications·2026
Same author

Massive barcode-free chemical screenings enable the discovery of bioactive macrocycles with passive membrane permeability.

Nature communications·2026
Same author

InstaNovo enables diffusion-powered de novo peptide sequencing in large-scale proteomics experiments.

Nature machine intelligence·2026
Same author

Bacterial Schlafen proteins mediate phage defence.

Nature microbiology·2026

Related Experiment Video

Updated: Dec 28, 2025

Genome Editing in Mammalian Cell Lines using CRISPR-Cas
07:56

Genome Editing in Mammalian Cell Lines using CRISPR-Cas

Published on: April 11, 2019

23.0K

Selective loading and processing of prespacers for precise CRISPR adaptation.

Sungchul Kim1, Luuk Loeff2, Sabina Colombo2

  • 1Kavli Institute of Nanoscience, Department of Bionanoscience, Delft University of Technology, Delft, The Netherlands. sungchulkim.kr@gmail.com.

Nature
|February 21, 2020
PubMed
Summary

CRISPR-Cas systems use the Cas1-Cas2 complex to acquire foreign DNA memory. This study reveals how Cas1-Cas2 selects DNA fragments and uses DnaQ exonucleases to trim them, ensuring correct spacer integration for prokaryotic immunity.

More Related Videos

Efficient PAM-Less Base Editing for Zebrafish Modeling of Human Genetic Disease with zSpRY-ABE8e
07:31

Efficient PAM-Less Base Editing for Zebrafish Modeling of Human Genetic Disease with zSpRY-ABE8e

Published on: February 17, 2023

1.5K
Using Sniper-Cas9 to Minimize Off-target Effects of CRISPR-Cas9 Without the Loss of On-target Activity Via Directed Evolution
11:37

Using Sniper-Cas9 to Minimize Off-target Effects of CRISPR-Cas9 Without the Loss of On-target Activity Via Directed Evolution

Published on: February 26, 2019

10.2K

Related Experiment Videos

Last Updated: Dec 28, 2025

Genome Editing in Mammalian Cell Lines using CRISPR-Cas
07:56

Genome Editing in Mammalian Cell Lines using CRISPR-Cas

Published on: April 11, 2019

23.0K
Efficient PAM-Less Base Editing for Zebrafish Modeling of Human Genetic Disease with zSpRY-ABE8e
07:31

Efficient PAM-Less Base Editing for Zebrafish Modeling of Human Genetic Disease with zSpRY-ABE8e

Published on: February 17, 2023

1.5K
Using Sniper-Cas9 to Minimize Off-target Effects of CRISPR-Cas9 Without the Loss of On-target Activity Via Directed Evolution
11:37

Using Sniper-Cas9 to Minimize Off-target Effects of CRISPR-Cas9 Without the Loss of On-target Activity Via Directed Evolution

Published on: February 26, 2019

10.2K

Area of Science:

  • Molecular Biology
  • Microbiology
  • Genetics

Background:

  • CRISPR-Cas immunity provides prokaryotes defense against foreign genetic elements.
  • The Cas1-Cas2 complex is crucial for establishing inheritable immune memory through spacer acquisition.
  • Mechanisms of prespacer selection and integration by Cas1-Cas2 remain incompletely understood.

Purpose of the Study:

  • To elucidate the mechanism by which Cas1-Cas2 selects prespacer precursors from foreign DNA.
  • To identify the enzymes involved in processing prespacers for integration.
  • To understand how correct spacer orientation is achieved during integration into the CRISPR locus.

Main Methods:

  • Single-molecule fluorescence microscopy with high spatiotemporal resolution.
  • Analysis of DNA selection by Cas1-Cas2 in various forms (ssDNA, partial duplexes).
  • Identification of DnaQ exonucleases in prespacer maturation.

Main Results:

  • Cas1-Cas2 selects prespacer precursors based on DNA length and protospacer adjacent motif (PAM) presence.
  • DnaQ exonucleases process selected precursors into mature, integration-ready prespacers.
  • Cas1-Cas2 protects the PAM sequence, leading to asymmetric trimming and correct spacer orientation.

Conclusions:

  • The study reveals a coordinated mechanism of prespacer precursor selection and PAM trimming by Cas1-Cas2.
  • This process ensures the accurate integration of functional spacers into CRISPR loci for adaptive immunity.
  • Findings provide critical insights into the molecular mechanisms of CRISPR-Cas adaptive immunity.