Scientists Perform Simultaneous Editing of Duplicated Loci in Soybean

The CRISPR-Cas9 system is a powerful tool for site-directed mutagenesis in crops. The team of Yuhei Kanazashi from Hokkaido University in Japan were successful in performing a simultaneous site-directed mutagenesis in two homoeologous loci in soybean (Glycine max), GmPPD1 and GmPPD2. These two genes are orthologs of Arabidopsis thaliana PEAPOD (PPD) gene.

Most of the T₁ plants generated had mutations in at least one of the targeted loci. Analysis of T₁ generation indicates that the mutations induced in the T₀ plant can be inherited by the T₁ generation. The team also induced new mutations in T₁ plants, which were then also detected in the T₂ generation. This indicates that continuous induction of mutations during T₁ plant development could increase the occurrence of mutations in germ cells.

Mutations in both GmPPD loci were also confirmed in at least 33% of the T₂ seeds examined. The mutants with mutations in both GmPPD1 and GmPPD2 exhibited dome-shaped trifoliate leaves, extremely twisted pods, and produced few seeds.

These results suggest that continuous induction of mutations in the succeeding generations of genome-edited plants can increase the efficiency of mutagenesis in duplicated loci in soybean.

For more information, read the article in Plant Cell Reports.