CRISPR/Cas9 Genome Engineering
CRISPR/Cas9 is a novel method to engineer genomes of live cells and organisms and has revolutionized many fields of developmental and cell biology. It is based on the expression of a nuclease called Cas9 and a short guide RNA (sgRNA). These two elements form a complex that targets sequences that share 20 bases of homology with the sgRNA, and have an NGG sequence following those 20 bases.
Once targeted, the CRISPR/Cas9 then creates a double strand break in the target sequence.
In eukaryote cells this double strand break can then be repaired by the Non-Homology End Joining (NHEJ) pathway that usually creates deletions or insertions at the break site.
Alternatively, this break can be repaired by the Homologous Recombination (HR) pathway using a sequence that shares homo0logy to the break site. By providing engineered homologous sequences, insertions, deletions and sequences replacements can be introduced to the genome.
Togather with colleagues, we adapted this system to C. elegans and now we have a system that enable us to create practically any custom mutation in a robust, fast and specific way. We use this method in our meiotic studies as well as continue to develop the technology and take it to the next level.