Abstract: Zinc finger proteins play an important role in drought stress. Although genes encoding these proteins have been cloned and identified in various plants, their functions and potential transcriptional mechanisms in Zoysia japonica are also not well understood. In the present study, the ZjZFN1 gene and its promoter were transformed into Arabidopsis thaliana by the inflorescence infection method, and then the transgenic A. thaliana was screened using glufosinate or hygromycin resistance screening and PCR identification. It was found that the promoter of ZjZFN1 can drive the expression of the GUS reporter gene system, and that the expression level of GUS genes under mannitol treatment was significantly higher than that of control plants. The results demonstrated that overexpression of ZjZFN1 in Arabidopsis reduced seed germination rate, and weakened plant adaptability to drought stress and plant growth status under drought stress. After drought treatment, malondialdehyde content was higher in plants overexpressing ZjZFN1 than that in the wild type plants, while the proline content in the transgenic plants was significantly lower than that in the wild type plants. Real-time fluorescence quantitative analysis showed that the over-expression of ZjZFN1 in Arabidopsis decreased the expression levels of peroxidase, superoxide dismutase, and pyrroline-5-carboxylate synthase enzymes and late embryogenesis abundant proteins, but increased the expression level of ascorbate peroxidase compared with control under drought treatment. This study indicates that overexpression of ZjZFN1 gene causes drought sensitivity in Arabidopsis, and provides a basis for further utilization of this gene.

Key words: Zoysia japonica, ZjZFN1 transcription factor, transgenic Arabidopsis, drought tolerance, resistant gene expression