Cloning of PsMYB62 and analysis of cadmium resistant in Potentilla sericea

Background: Potentilla sericea is a heavy metal hyperaccumulator landscaping plant. MYB transcription factors play an important role in regulating plant stress response to adversity. However, there are few studies on MYB transcription factors in stress tolerance in Potentilla sericea. In this study, the PsMYB62 gene was successfully cloned from Potentilla sericea. Methods: Bioinformatic analysis and real-time quantitative PCR (qPCR) methods were used to evaluate this gene. The transgenic A. thaliana were obtained by flower dipping and the gene function was identified by determining physiological indicators under cadmium stress. Results: The open reading frame of PsMYB62 is 942 bp, which encodes 313 amino acids (aa) and belongs to the R2R3 MYB transcription factor. The plant overexpression vector PBI121-PsMYB62-GFP was constructed and successfully transferred into A. thaliana. The relative expression level of PsMYB62 was significantly increased by CdCl2, NaCl, ABA, and mannitol treatments. The germination rate of transgenic seeds was higher than those of wild type (WT) and empty vector (EV) under different concentrations of cadmium treatment. Upon treatment with 100 mu mol.L-1 of CdCl2.2.5H(2)O, the activities of superoxide dismutase (SOD), peroxidase (POD), and catalase (CAT) in the transgenic plants were significantly higher than those in the WT and EV. The contents of H2O2, O-2(center dot-) and malondialdehyde (MDA) in transgenic lines were increased, but lower than those in WT and EV. The expression levels of AtGSH, AtPCS, and AtNAS4 that were related to the regulation of cadmium were increased, but the expression levels of transgenic lines were higher than those of WT and EV. Conclusion: The above results showed that PsMYB62 could be induced by cadmium and could improve the cadmium resistance of plants.