Plant genome editing using engineered nucleases and success of CRISPR/Cas9 system

Development of new plant breeding techniques have facilitated easy manipulation of plants at genetic level. Clustered Regularly Interspaced Short Palindromic Repeats (CRISPR)/CRISPR associated protein9 (Cas9) system is a valuable addition in programmable nucleases. The CRISPR/Cas9 system uses an RNA component to recognize a target DNA sequences and it has shown promising results with respect to simultaneous editing of multigenic plant traits. In this review, components of CRISPR/Cas9, their construction and its methods of delivery to plant cells are analyzed. Variation in nucleotide sequence of the protospacer adjacent motif, codon optimization and progress in web-based bioinformatic tools, will make CRISPR/Cas9 systems more efficient for plants. Development and optimization of protocols to efficiently target all plant species is still under development. Along with this, methods to inspect induced mutation and efficiency of the system have also been reviewed. Auxiliary improvements and understanding are still required to expand the CRISPR/Cas9 systems to target complex genome architectures and epigenetic elements