Crop Biotech Update

Researchers Generate Arabidopsis GGAT1 Mutants Using CRISPR

February 7, 2018

Glutamate:glyoxylate aminotransferase 1 (GGAT1) is a key enzyme in plants' photorespiration pathway. However, the mechanism of its regulation is unknown. With the generation of mutated ggat1 from the Col-0 genetic background, mutated ggat1 from the Ler genetic background should be useful in the study of GGAT1. However, the latter are not currently available.

The team of Yaping Liang from the South-China Agricultural University used CRISPR-Cas9 to generate ggat1 mutants from the Ler genetic background. The team designed two single-guide RNAs (sgRNAs) that target GGAT1. These were then inserted into flowering Arabidopsis (Ler) plants via Agrobacterium tumefaciens-mediated transformation. Thirteen GGAT1-edited T1 lines were generated from the transformed plants. From these T1 plants, two homozygous T2 mutants were generated.

The mutations were found to be stable through generations. In addition, the genetic segregation of the mutations followed the Mendelian segregation, and no off-target mutations were detected. The two independent ggat1 mutants had similar photorespiration phenotypes and downregulated GGAT enzyme activity.

CRISPR-Cas9 was successful in generating genetically stable Arabidopsis ggat1 Ler mutants. These will be useful in further research studies on GGAT1 enzyme.

For more information on this study, read the article in Transgenic Research.