Isolation and Characterization of a Novel Ethylene Response Transcriptional Factor GsERF6(GsERF71) from Glycine soja

The saline-alkaline stresses in soils inhibit plant growth and development severely all over the word, but the mechanism of how plants resist it is still unclear. In this study, we cloned and characterized an alkaline response gene GsERF71 from Glycine soja (G07256), which is a typical high alkaline stress resistant plant species. We found GsERF71 could be highly induced by salt and alkali stresses in both the roots and leaves of Glycine soja. GsERF71-GFP fusion protein was localized in the nuclei of onion epidermis cells and could activate the reporters in yeast cells. Yeast one-hybrid assay indicated that GsERF71 could specifically bind with the cis-acting elements of DRE-motif and GCC-box, suggesting that GsERF71 may participate in the regulation of transcription of the relevant biotic and abiotic stress-related genes. The Arabidopsis overexpressing GsERF71 had better tolerance to bicarbonate stress generated by NaHCO3 and KHCO3 compared with wild type Arabidopsis. Quantitative real-time PCR analysis demonstrated that the typical stress-related genes including RD29A, COR47, KIN1 and H+-ATPase were up-regulated in the transgenic lines. The auxin biosynthetic-related genes like ASA1, ASB1, PAT1 and PAI1 were down-regulated in the transgenic plants compared to the wild type plants. All the results suggested that GsERF71 enhanced plants resistance to bicarbonate stress may be through activating the downstream stress-responsive genes and down-regulating the auxin accumulation.