Mechanism of SnRK2.2/2.3 kinase involved in regulating cadmium stress response in Arabidopsis thaliana

Abstract:

In order to explore the molecular mechanism of Arabidopsis SnRK2.2 and SnRK2.3 genes in response to Cd stress. Wild-type (WT), double mutant SnRK2.2/2.3, overexpressing SnRK2.2 and overexpressing SnRK2.3 transgenic plants were used as materials to study the relationship between SnRK2.2 and SnRK2.3 genes and Cd stress response. The study found that the overexpression of SnRK2.2 and SnRK2.3 genes can improve the tolerance of Arabidopsis Cd, which showed that the overexpression of the two genes can reduce the accumulation of Cd, malondialdehyde (MDA) and reactive oxygen species (ROS) and increase the activities of antioxidant enzymes CAT, POD and SOD. qRT-PCR results showed that under Cd stress, the expression levels of iron-regulated transporter IRT1 transcription factors FIT, bHLH038 and bHLH039 were significantly inhibited, and the expressions levels of ABA synthesis-related genes AAO3 and NCED3 were significantly up-regulated in the two overexpressed plants. Under Cd stress, the ABA content of the two overexpressed plants was significantly higher than that of the WT and double mutant. These results suggested that when Arabidopsis was under Cd stress, SnRK2.2 and SnRK2.3 genes reduced the uptake of Cd by down-regulating the expression of the IRT1 gene, and alleviated the toxicity of Cd to plants by increasing the content of endogenous ABA.