professor National Chiayi University Chiayi City, Chiayi, Taiwan (Republic of China)
Body of Abstract: This study focuses on the physiological function of the OsAKR5 gene, a member of the aldo-keto reductase (AKR) family. AKR are NADPH-dependent enzymes, that involved in cellular detoxification, sugar alcohol biosynthesis, and stress tolerance. In plants, most AKRs belong to the 4C subgroup (AKR4Cs). We identified a new OsAKR gene T-DNA knockout mutant line (KdAKR5), two OsAKR5 overexpression transgenic lines (OxAKR5), and further to initiate the OsAKR5 knockdown line by CRISPR/Cas9 gene editing technology. We introduced double sgRNA through Agrobacterium transformation to specifically cleave the DNA sequence of the OsAKR5 gene. It obtained twenty T0 transformants (criAKR5) with six different edited genotypes and the editing efficiency is 95%. The KdAKR5 mutant displayed delayed growth, reduced plant height, decreased tillering, and increased sensitivity to drought stress compared to wild type. To assess stress tolerance, WT, KdAKR5, OxAKR5, and criAKR5 rice seedlings were subjected to treatments of salt and drought stress. The overexpression of the OsAKR5 gene exhibited better plant growth performance and higher expression levels under osmotic stress compared to KdAKR5 and criAKR5. In contrast, the criAKR5 plants showed lower growth performance and expression levels than the wild type. In conclusion, we identified a novel OsAKR5 gene is positive correlated to rice development and abiotic stresses tolerance.