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
CISPR-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