Molecular Characterization and Drought Resistance of GmNAC3 Transcription Factor in (L.) Merr.

Soybean transcription factor GmNAC plays important roles in plant resistance to environmental stresses. In this study, was cloned in the drought tolerant soybean variety "Jiyu47", with the molecular properties of GmNAC3 characterized to establish its candidacy as a NAC transcription factor. The yeast self-activation experiments revealed the transcriptional activation activity of GmNAC3, which was localized in the nucleus by the subcellular localization analysis. The highest expression of was detected in roots in the podding stage of soybean, and in roots of soybean seedlings treated with 20% PEG6000 for 12 h, which was 16 times higher compared with the control. In the transgenic soybean hairy roots obtained by the -mediated method treated with 20% PEG6000 for 12 h, the activities of superoxide dismutase, peroxidase, and catalase and the content of proline were increased, the malondialdehyde content was decreased, and the expressions of stress resistance-related genes (i.e., , , , and ) were up-regulated. These expression patterns were confirmed by transgenic with the overexpression of . This study provided strong scientific evidence to support further investigation of the regulatory function of in plant drought resistance and the molecular mechanisms regulating the plant response to environmental stresses.