Scientists Identify Efficient Guides to Develop Herbicide Tolerant Tomatoes Using CRISPR-Cas9

Scientists from the Republic of Korea demonstrated the use of single guide RNAs (sgRNAs) as guides for CRISPR-Cas9 crop transformation to breed herbicide-resistant crops, particularly for the tomato. This new information provides more options for scientists who use gene editing tools to develop crops with more desirable traits.

The scientists focused on three target genes for herbicides, namely phytoene desaturase (pds), acetolactate synthase (ALS), and 5-Enolpyruvylshikimate-3-phosphate synthase (EPSPS). These were the targets of sgRNAs to be used with the CRISPR-Cas9 system in the tomato. The sgRNAs were first tested for efficiency through Agrobacterium mediated transient expression in tomato cotyledons. The scientists then documented that one sgRNA for pds had no significant efficiency, but three sgRNAs for ALS had significant efficiency, and that one sgRNA for EPSPS also had an editing efficiency. These were the pieces of evidence that the editing of the target sites could be achieved in the transformation process.

Further tests resulted in 19 transgenic tomatoes which were successfully edited for two ALS genes. It was concluded that performing sgRNA efficiency tests before crop transformation was useful to scientists, and that CRISPR-Cas9 can successfully help breed herbicide-resistant crops.

For more information, read the article published by Applied Biological Chemistry.