Search research articles

ABOUT JoVE

Overview Leadership Blog JoVE Help Center

AUTHORS

Publishing Process Editorial Board Scope & Policies Peer Review FAQ Submit

LIBRARIANS

Testimonials Subscriptions Access Resources Library Advisory Board FAQ

RESEARCH

JoVE Journal Methods Collections JoVE Encyclopedia of Experiments Archive

EDUCATION

JoVE Core JoVE Business JoVE Science Education JoVE Lab Manual Faculty Resource Center Faculty Site

Terms & Conditions of Use

Related Concept Videos

CRISPR/Cas9 Genome Editing

CRISPR/Cas9 Genome Editing

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...

CRISPR and crRNAs

CRISPR and crRNAs

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...

CRISPR

CRISPR

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...

The Antiviral System of Bacteria and Archaea: CRISPR

The Antiviral System of Bacteria and Archaea: CRISPR

CRISPR stands for Clustered Regularly Interspaced Short Palindromic Repeats is a adaptive immune system found in bacteria and archaea that protects against viral infections. This system enables prokaryotic cells to identify, remember, and neutralize foreign genetic elements, primarily bacteriophages, by storing fragments of the invader’s DNA as a genetic memory.The CRISPR immune response begins during an initial infection. Cas (CRISPR-associated) proteins play a central role in this...

Homologous Recombination

Homologous Recombination

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...

Conservative Site-specific Recombination and Phase Variation

Conservative Site-specific Recombination and Phase Variation

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...

You might also read

Related Articles

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

Sort by

Same author

Polyphosphate acts as an architectural regulator of carbon fixation and nucleoid structure in cyanobacteria.

bioRxiv : the preprint server for biology·2026

Same author

High-throughput characterization of Mycobacterium tuberculosis gene function across diverse conditions.

PLoS biology·2026

Same author

Using Cryogenic Electron Tomography (cryoET) to Determine Rubisco Polymerization Constants in α-Carboxysomes.

bioRxiv : the preprint server for biology·2026

Same author

Mapping cis-regulatory mutations at scale in sorghum enables modulation of gene expression.

Nature biotechnology·2026

Same author

Engineered TnpB genome editors for plants and human cells identified by ribonucleoprotein mutational scanning.

Nature biotechnology·2026

Same author

Stable Inheritance of Transgene and Yellow Fluorescent Protein Gene Expression in Progeny of Transgenic Cacao (<i>Theobroma cacao</i>) Plants.

Plants (Basel, Switzerland)·2026

Search research articles

Related Experiment Video

Updated: Aug 20, 2025

Enhanced Genome Editing with Cas9 Ribonucleoprotein in Diverse Cells and Organisms

Enhanced Genome Editing with Cas9 Ribonucleoprotein in Diverse Cells and Organisms

Published on: May 25, 2018

Diverse virus-encoded CRISPR-Cas systems include streamlined genome editors.

Basem Al-Shayeb¹, Petr Skopintsev², Katarzyna M Soczek²

¹Department of Plant and Microbial Biology, University of California, Berkeley, CA, USA; Innovative Genomics Institute, University of California, Berkeley, CA, USA; Department of Earth and Planetary Science, University of California, Berkeley, CA, USA; Department of Environmental Science, Policy and Management, University of California, Berkeley, CA, USA; University of Melbourne, Melbourne, Australia; Department of Chemistry, University of California, Berkeley, CA, USA; MBIB Division, Lawrence Berkeley National Laboratory, Berkeley, CA, USA; Gladstone Institutes, University of California, San Francisco, CA, USA.

|November 24, 2022

Summary

CRISPR-Cas systems, typically found in microbes, are also discovered in bacteriophages as compact anti-viral tools. These phage-encoded systems, including novel Casλ nucleases, show potential for genome editing in plants and human cells.

Keywords:

CRISPR CRISPR-Cas anti-viral enzyme genome editing genome editor metagenomics phage structure tool

More Related Videos

Substrate Generation for Endonucleases of CRISPR/Cas Systems

Substrate Generation for Endonucleases of CRISPR/Cas Systems

Published on: September 8, 2012

Selection-dependent and Independent Generation of CRISPR/Cas9-mediated Gene Knockouts in Mammalian Cells

Selection-dependent and Independent Generation of CRISPR/Cas9-mediated Gene Knockouts in Mammalian Cells

Published on: June 16, 2017

Related Experiment Videos

Last Updated: Aug 20, 2025

Enhanced Genome Editing with Cas9 Ribonucleoprotein in Diverse Cells and Organisms

Enhanced Genome Editing with Cas9 Ribonucleoprotein in Diverse Cells and Organisms

Published on: May 25, 2018

Substrate Generation for Endonucleases of CRISPR/Cas Systems

Substrate Generation for Endonucleases of CRISPR/Cas Systems

Published on: September 8, 2012

Selection-dependent and Independent Generation of CRISPR/Cas9-mediated Gene Knockouts in Mammalian Cells

Selection-dependent and Independent Generation of CRISPR/Cas9-mediated Gene Knockouts in Mammalian Cells

Published on: June 16, 2017

Area of Science:

Microbiology
Molecular Biology
Genetics

Background:

CRISPR-Cas systems are microbial defense mechanisms against viruses.
These systems utilize RNA-guided pathways for adaptive immunity.

Purpose of the Study:

To investigate the presence and diversity of CRISPR-Cas systems in bacteriophages.
To characterize novel CRISPR-Cas enzymes, particularly from bacteriophages, for genome editing applications.

Main Methods:

Genome-resolved metagenomics to identify phage-encoded CRISPR systems.
Cryo-electron microscopy to determine the structure of Casλ-crRNA-DNA complexes.
Functional assays in mammalian, Arabidopsis, and wheat cells to assess genome editing capabilities.

Main Results:

CRISPR-Cas systems were identified in diverse bacteriophages, functioning as compact anti-viral systems.
New Cas9-like proteins and 44 families related to type V CRISPR-Cas systems, including the Casλ nuclease, were discovered.
The Casλ-crRNA-DNA structure revealed a unique architecture enabling genome editing in various cell types.

Conclusions:

Bacteriophages represent a novel source of diverse CRISPR-Cas systems.
Phage-derived CRISPR-Cas enzymes, such as Casλ, offer promising tools for genome editing in plants and human cells.