New Platform Stacks Multiple Traits in Crops

A new genome engineering platform allows for stacking multiple desirable traits in crops. The platform combines gene knockout, precise sequence editing, and chromosome engineering. This development addresses the time-consuming nature of current crop breeding strategies.

Researchers at the Institute of Genetics and Developmental Biology of the Chinese Academy of Sciences developed the platform. Gao Caixia led the research team. Their findings were published in *Nature Biotechnology*.

The team first created a gene knockout tool called twin prime editing-mediated gene knockout (TKO). This tool precisely inserts a stop codon cluster at a target site. TKO effectively disrupts genes by installing stop codons, avoiding common in-frame insertions or deletions seen in other systems.

TKO showed high efficiency in monocot crops like rice, wheat, and maize. In regenerated rice plants, the average efficiency for single gene knockout reached 96.8 percent. Researchers also developed ten orthogonal TKO systems to prevent cross-editing between different genetic locations. These systems allow for simultaneous knockout of up to ten genes.

Building on TKO, the researchers developed two integrated genome engineering platforms, TRIM1 and TRIM2, collectively known as TRIM. TRIM1 combines TKO with prime editing for sequence modification. This enables simultaneous gene knockout, base substitution, insertion, deletion, duplication, and inversion. TRIM2 incorporates a prime editor–Cre recombinase fusion protein. This allows for kilobase-scale DNA insertion, replacement, deletion, inversion, and chromosomal translocation.

TRIM integrates various genome editing capabilities into one platform. This unified approach offers a powerful method for rapidly combining multiple favorable alleles. It enhances precision breeding for complex traits in monocot crops.