BACKGROUND Microinjection of clustered regulatory interspaced short palindromic repeat (CRISPR)/CRISPR-associated protein 9 (Cas9)-related RNA and DNA into fertilized eggs is a novel approach for creating gene-modified mice. Blastocysts obtained just before implantation may be appropriate for testing the fidelity of CRIPSR/Cas9-mediated genome editing because they can be individually handled in...

Knockout of genes with CRISPR/Cas9 is a newly emerged approach to investigate functions of genes in various organisms. We demonstrate that CRISPR/Cas9 can mutate endogenous genes of the ascidian Ciona intestinalis, a splendid model for elucidating molecular mechanisms for constructing the chordate body plan. Short guide RNA (sgRNA) and Cas9 mRNA, when they are expressed in Ciona embryos by mean...

The type II clustered regularly interspaced short palindromic repeats (CRISPR)/CRISPR-associated (Cas) system has emerged recently as a powerful method to manipulate the genomes of various organisms. Here, we report a toolbox for high-efficiency genome engineering of Drosophila melanogaster consisting of transgenic Cas9 lines and versatile guide RNA (gRNA) expression plasmids. Systematic evalua...

Understanding the biological function behind key proteins is of great concern in Atlantic salmon, both due to a high commercial importance and an interesting life history. Until recently, functional studies in salmonids appeared to be difficult. However, the recent discovery of targeted mutagenesis using the CRISPR/Cas9 (clustered regularly interspaced palindromic repeats/CRISPR-associated) sys...

CRISPR/Cas9 is a rapidly developing genome editing technology that has been successfully applied in many organisms, including model and crop plants. Cas9, an RNA-guided DNA endonuclease, can be targeted to specific genomic sequences by engineering a separately encoded guide RNA with which it forms a complex. As only a short RNA sequence must be synthesized to confer recognition of a new target,...

W e would like to thank Dr. Wong for the response to our article “No time to waste—the ethical challenges created by CRISPR”. Dr. Wong’s letter addresses a question about the relationship between biology and society: that “prevailing papers” on CRISPR-Cas9 rarely emphasize understanding the microbiological processes that make CRISPR-Cas9 an effective defensive mechanism. Instead, scientists and...

The CRISPR/Cas9 system is an efficient genome-editing platform for diverse eukaryotic species, including plants. Recent work harnessed CRISPR/Cas9 technology to engineer resistance to geminiviruses. Here, we discuss opportunities, emerging developments, and potential pitfalls for using this technology to engineer resistance against single and multiple geminivirus infections in plants.

High efficiency, homology-directed genome editing in C. elegans using CRISPR/Cas9 ribonucleoprotein complexes Alexandre Paix, Andrew Folkmann, Dominique Rasoloson, Geraldine Seydoux HHMI and Dept of Molecular Biology and Genetics, Johns Hopkins University, School of Medicine, Baltimore MD 21205, USA Running title: Genome editing in C. elegans using CRISPR/Cas9 RNP complexes

Applying clustered regularly interspaced short palindromic repeats (CRISPR)/CRISPR associated protein 9 (Cas9)-mediated mutagenesis to primary mouse immune cells, we used high-fidelity single guide RNAs (sgRNAs) designed with an sgRNA design tool (CrispRGold) to target genes in primary B cells, T cells, and macrophages isolated from a Cas9 transgenic mouse line. Using this system, we achieved a...

CRISPR-Cas9 technology has rapidly changed the landscape for how biologists and bioengineers study and manipulate the genome. Derived from the bacterial adaptive immune system, CRISPR-Cas9 has been coopted and repurposed for a variety of new functions, including the activation or repression of gene expression (termed CRISPRa or CRISPRi, respectively). This represents an exciting alternative to ...