Germ-line-Specific CRISPR-Cas9 Systems Improve the Production of Heritable Gene Mutations in Arabidopsis

CRISPR/Cas9 is widely used for targeted gene modifications in plants. The system has two components, a single-guide RNA (sgRNA) for target DNA recognition and the CRISPR-associated protein 9 (Cas9) for DNA cleavage. However, while ubiquitously expressed CRISPR/Cas9 systems (UC) generate targeted gene modifications with high efficiency, only those produced in reproductive cells are passed on to the next generation.

Yanfei Mao of the Chinese Academy of Sciences, together with a team of researchers, reports the design and characterization of a germ-line-specific Cas9 system (GSC) for Arabidopsis gene modification in male gametocytes.

Two genes were targeted by both systems, UC and GSC, for analysis. Mutations generated by the GSC system were rare in T1 plants, but were abundant in the T2 generation. Majority of the T2 mutant population generated using the UC system were chimeras while only 29% of those produced via GSC were chimeras.

Further analysis of the T2 population showed that the heritable gene mutations were 37% higher in the GSC system compared to the UC system.

For more on this study, read the article in Plant Biotechnology Journal.