Researchers Perform Targeted Mutation and Gene Replacement in Tomato

Targeted genome editing is becoming an increasingly important tool for precise plant breeding. A team led by Tal Dahan‐Meir from Weizmann Institute of Science in Israel used a combination of the CRISPR‐Cas system and the bean yellow dwarf virus rolling circle replicon to facilitate targeted mutagenesis and gene replacement in tomato.

The team chose to target the carotenoid isomerase (CRTISO) and phytoene synthase 1 (PSY1) genes from the carotenoid biosynthesis pathway due to their easily detectable phenotype. The team used the geminiviral replicon amplification to provide a large amount of donor template for gene replacement experiment.

The team achieved precise modification of the CRTISO and PSY1 loci at an efficiency of up to 90%. In the gene replacement experiment, the target was a crtiso allele that contained a 281bp deletion. The deletion was repaired using the donor template through homologous recombination. The gene replacement experiment was successful in 25% of the plants transformed.

This shows that efficient targeted mutagenesis and gene replacement can be achieved using a single construct and can be adapted to other tomato genes as well as other crops.

For more information, read the article in The Plant Journal.