NAC Transcription Factor GmNAC12 Improved Drought Stress Tolerance in Soybean

Abstract

NAC transcription factors (TFs) could regulate drought stresses in plants; however, the function of NAC TFs in soybeans remains unclear. To unravel NAC TF function, we established that <i>GmNAC12</i>, a NAC TF from soybean (<i>Glycine max</i>), was involved in the manipulation of stress tolerance. The expression of <i>GmNAC12</i> was significantly upregulated more than 10-fold under drought stress and more than threefold under abscisic acid (ABA) and ethylene (ETH) treatment. In order to determine the function of <i>GmNAC12</i> under drought stress conditions, we generated <i>GmNAC12</i> overexpression and knockout lines. The present findings showed that under drought stress, the survival rate of <i>GmNAC12</i> overexpression lines increased by more than 57% compared with wild-type plants, while the survival rate of <i>GmNAC12</i> knockout lines decreased by at least 46%. Furthermore, a subcellular localisation analysis showed that the <i>GmNAC12</i> protein is concentrated in the nucleus of the tobacco cell. In addition, we used a yeast two-hybrid assay to identify 185 proteins that interact with <i>GmNAC12</i>. Gene ontology (GO) and KEGG analysis showed that <i>GmNAC12</i> interaction proteins are related to chitin, chlorophyll, ubiquitin-protein transferase, and peroxidase activity. Hence, we have inferred that <i>GmNAC12</i>, as a key gene, could positively regulate soybean tolerance to drought stress.