Simple Heat Treatment Boosts CRISPR Efficiency in Arabidopsis

Ehime University researchers reported a simple heat treatment that can increase CRISPR efficiency in Arabidopsis. Their findings are published in the Plant and Cell Physiology journal.

In editing the genome of Arabidopsis, the SpCas9 and guide RNA genes are commonly introduced into the genome by the floral dip method. One of the advantages of this method is that genome-edited plants can be isolated effortlessly. However, mutation efficiency in Arabidopsis using SpCas9 is not as high as that achieved in rice and tobacco, which are subjected to a tissue culture step.

The researchers compared four promoters and found that the parsley UBIQITIN promoter is significantly active in Arabidopsis meristem tissue. They also explored if a simple heat treatment could improve mutation efficiency in Arabidopsis. Results showed that just one heat treatment at 37 °C for 24 hours increased the mutation efficiency at all four target sites from 3% to 42%, 43% to 62%, 54% to 75%, and 89 to 91%, respectively, without detectable off-target mutations.

Based on the results, the researchers recommend heat treatment of plate-grown plants at 37 °C for 24 hours to increase the efficiency of CRISPR-Cas9-mediated mutagenesis in Arabidopsis.

Read the accepted manuscript in the Plant and Cell Physiology journal.