[CRISPR/Cas9-based genome editing systems and the analysis of targeted genome mutations in plants]

Targeted genomic editing technologies use programmable DNA nucleases to cleave genomic target sites, thus inducing targeted mutations in the genomes. The newly prevailed clustered regularly interspaced short palindromic repeats/CRISPR-associated protein 9 (CRISPR/Cas9) system that consists of the Cas9 nuclease and single guide RNA (sgRNA) has the advantages of simplicity and high efficiency as compared to other programmable DNA nuclease systems such as zinc finger nucleases (ZFNs) and transcription activator like effector nucleases (TALENs). Currently, a number of cases have been reported on the application of the CRISPR/Cas9 genomic editing technology in plants. In this review, we summarize the strategies for preparing the Cas9 and sgRNA expression constructs, the transformation method for obtaining targeted mutations, the efficiency and features of the resulting mutations and the methods for detecting or genotyping of the mutation sites. We also discuss the existing problems and perspectives of CRISPR/Cas9-based genomic editing in plants.