Cas9 is an RNA guided DNA nuclease associated with the type II CRISPR/Cas adaptive immune systems. In prokaryotes, the CRISPR/Cas9 system protects the viruses and plasmids by targeting foreign nucleic acids and with complementary single-stranded RNA. This localizes the Cas9 nuclease to the target DNA sequence, introducing double-strand breaks at specific locations with the genomic DNA.
The CRISPR/Cas9 system has the potential to transform developmental biology by providing a simple, efficient method to precisely manipulate the genome of virtually any developing organism.
