CRISPR/Cas9: An RNA-guided highly precise synthetic tool for plant genome editing.

CRISPR/Cas9 is a newly developed and naturally occurred genome editing tool, which is originally used by bacteria for immune defence. In the past years, it has been quickly employed and modified to precisely edit genome sequences in both plants and animals. Compared with the well-developed zinc finger nucleases (ZFNs) and transcription activator-like effector nucleases (TALENs), CRISPR/Cas9 has lots of advantages, including easier to design and implement, higher targeting efficiency, and less expensive. Thus, it is becoming one of the most powerful tools for knockout of an individual gene as well as insertion of one gene and/or control of gene transcription. Studies have shown that CRISPR/Cas9 is a great tool to edit many genes in a variety of plant species, including the model plant species as well as agriculturally important crops, such as cotton, maize, wheat, and rice. CRISPR/Cas9-based genome editing can be used for plant functional studies and plant improvement to yield, quality, and tolerance to environmental stress.