miR397-LACs mediated cadmium stress tolerance in Arabidopsis thaliana

Cadmium (Cd) is a non-essential heavy metal, assimilated in plant tissue with other nutrients, disturbing the ions’ homeostasis in plants. The plant develops different mechanisms to tolerate the hazardous environmental effects of Cd. Recently studies found different miRNAs that are involved in Cd stress. In the current study, miR397 mutant lines were constructed to explore the molecular mechanisms of miR397 underlying Cd tolerance. Compared with the genetically modified line of overexpressed miR397 (artificial miR397, amiR397), the lines of downregulated miR397 (Short Tandem Target Mimic miR397, STTM miR397) showed more substantial Cd tolerance with higher chlorophyll a & b, carotenoid and lignin content. ICP-OES revealed higher cell wall Cd and low total Cd levels in STTM miR397 than in the wild-type and amiR397 plants.