Researchers Develop Gene Editing Toolkit for Trait Stacking in Soybean

Guangzhou University researchers in China and partners reported a robust multiplex CRISPR-Cas12i3-5M system for trait stacking in soybean. The findings are published in the Journal of Integrative Plant Biology.

The researchers developed an optimized, high-efficiency multiplex gene-editing toolkit specifically for soybean, which uses a modified Cas12i3 variant (Cas12i3-5M) driven by a strong endogenous soybean promoter (GmM4pro) to overcome the typically low editing efficiency of Cas12i in dicot plants. The system demonstrated the ability to target and edit up to 13 different genomic sites simultaneously. Using a compact "tRNA-crRNA" processing strategy, it achieved editing efficiencies ranging from 30% to over 85% across multiple loci in soybean hairy roots, significantly outperforming previous Cas12 versions.

The team targeted two major quality traits at once: high oleic acid content and low beany flavor. They simultaneously knocked out five genes: two fatty acid desaturase genes and three lipoxygenase genes. This led to a dramatic increase in oleic acid and a near-total elimination of "beany" flavor compounds, making the beans more palatable for human consumption. Despite the complex genetic changes, the edited soybean plants maintained normal growth and development.

Read the research article in the Journal of Integrative Plant Biology.