The Soybean Basic Helix-Loop-Helix Transcription Factor ORG3-Like Enhances Cadmium Tolerance via Increased Iron and Reduced Cadmium Uptake and Transport from Roots to Shoots

• DOI: 10.3389/fpls.2017.01098
• Publication Date: 2017-06-27T23:46:50Z
• Authors: Zhaolong Xu; Xiaoqing Liu; Xiaolan He; Ling Xu; Yihong Huang; Hongbo Shao; Dayong Zhang; Boping Tang; Hongxiang Ma
• Keywords: Chlorosis; Basic helix-loop-helix; Ectopic expression

Cadmium (Cd) is one of the most dangerous heavy metal pollutants in environment and toxic to animal plant cells. On other hand, iron (Fe) an essential element for growth development. The chlorosis leaves under cadmium stress similar typical symptom deficiency. Recently, several Arabidopsis basic/helix-loop-helix (bHLH) transcription factors have been identified that are involved interactions between Cd Fe. In present study, over-expression ORG3-like gene GmORG3, a bHLH factor OBP3-responsive (ORG), enhanced tolerance stabilized Fe homeostasis. domain analysis GmORG3 showed protein contains conserved 61-residue belonging subfamily II. Moreover, subcellular localization experiments nucleoprotein. was transcribed only soybean roots significantly induced by external plants. Heterologous expression yeast. Furthermore, overexpression mosaic seedlings using hairy root system overexpressing plants increased translocation ratio but reduced from shoots. addition, ectopic tobacco phytotoxic effects deficiency, including blockage elongation decreased chlorophyll content. By integrating all these results, we found plays important role response stress. results provide new insights into molecular mechanisms soybean.