Overexpression of ethylene response factors VaERF080 and VaERF087 from Vitis amurensis enhances cold tolerance in Arabidopsis

Low temperature is a vital environmental factor that affects plant growth, development and crop yields. Ethylene response factor (ERF) is a plant specific transcription factor with important roles in stress adaptation. However, the regulatory mechanism on how grapevine responds to cold stress is still unclear. In this study, we isolated and characterized two ERF genes from Vitis amurensis designated as VaERF080 and VaERF087. The function of these two genes was investigated in transgenic Arabidopsis. We found that both VaERF080 and VaERF087 were induced by cold stress and ethylene. The overexpression of these genes in Arabidopsis resulted in enhanced cold tolerance. The VaERF080- and VaERF087-overexpressing (OE) Arabidopsis lines showed lower levels of malondialdehyde (MDA) content and higher activities of superoxide dismutase (SOD), peroxidase (POD), and catalase (CAT) under cold stress compared to wild-type (WT) Arabidopsis. Nine representative cold-responsive genes, CBF1, CBF2, ICE1, ZAT12, KIN1, SIZ1, RD29A, COR15A, and COR47, were significantly upregulated in OE Arabidopsis. These results revealed that both VaERF080 and VaERF087 may improve the cold tolerance of transgenic Arabidopsis through increasing antioxidant enzyme activities and regulating the expression of cold-related genes.