CRISPR-Cas9-Mediated Gene Replacement Generates Long-shelf Life Tomato Lines

Breeders have long dreamed of developing genetically-enhanced breeding elites with value-adding performance as quickly as possible. With the present gene editing technologies, such as the CRISPR-Cas9 system, there is a reasonable expectation towards quickly achieving breeding goals.

To evaluate the possible application of CRISPR-Cas9 on accelerating plant breeding, the team of Qing-hui Yu from Xinjiang Academy of Agricultural Science in China aimed to develop tomatoes with long shelf-life through gene replacement via homology directed repair (HDR) using CRISPR-Cas9.

The team aimed to replace the tomato ALC gene with a recessive alc gene. The average mutation frequency reached 72.73%. However, low replacement efficiency (7.69%) was achieved in T₀ transgenic plants. No homozygous recessive mutations were detected in T₀ plants.  The heterozygous mutants stably transmitted the mutation to the T₁ generation for segregation. The desired alc homozygous mutants were achieved in T₁ generations.

This was further confirmed by characterization, highlighted by excellent storage performance. These results prove that CRISPR-Cas9-induced gene replacement via HDR could be a valuable method for breeding elite lines in tomato.

For more on this study, read the article in Scientific Reports.