CRISPR-Cas9: Biological Roles, Mechanisms, And Evolution

The RNA-programmable CRISPR-Cas9 system has recently emerged as a transformative technology for rapid and efficient targeted genome editing, chromosomal marking and gene regulation. In this system, the endonuclease Cas9 or catalytically inactive Cas9 variants are programmed with single guide RNAs to target site-specifically any DNA sequence of interest. The system is efficient, versatile and easily programmable. DNA targeting by CRISPR-Cas9 has been quickly and broadly adopted by the scientific community to edit and silence genomes in a large variety of cells and organisms, including human cells, plants and mice. I will discuss the biological roles of CRISPR-Cas9, the mechanisms involved, the evolution of type II CRISPR-Cas components in bacteria and the applications of CRISPR-Cas9 as a novel genome engineering technology.