Biotech Updates

Agrobacterium-delivered CRISPR-Cas9 System for Genome Editing of Wheat

February 6, 2019

Researchers have been using the CRISPR-Cas9 system to edit the genomes of important crops such as wheat. Despite the tractability in designing this system, the efficacy of the tool is also dependent on the DNA delivery method. The most common delivery method is biolistics based transformation but due to the high frequency of gene silencing linked with high copy transgenes and low edit rate in wheat, a large population of transgenic plants are needed for recovery of desired mutations. This led Zhengzhi Zhang from the University of Missouri and team to develop an Agrobacterium-delivered CRISPR-Cas9 system in wheat.

The reported system includes a wheat codon optimized Cas9 driven by a maize ubiquitin gene promoter and a guide RNA cassette driven by wheat U6 promoters in a single binary vector. Using the system, they have developed 69 edit mutants for four grain-regulatory genes in three generations at an average edit rate of 10% without detecting off-target mutations in the most Cas9-active plants.

Based on the positive results of the study, it has proven that the Agrobacterium-delivered CRISPR-Cas9 system could be used for wheat genome editing, which only needs a small number of transformation events.

Read the research article from the Plant Biotechnology Journal.