TaMADS2-3D, a MADS transcription factor gene, regulates phosphate starvation responses in plants

• DOI: 10.1016/j.cj.2021.03.020
• Publication Date: 2021-05-07T03:25:09Z
• Authors: Yingchun Han; Na Liu; Chuang Li; Shuaiwu Wang; Lihua Jia; Rui Zhang; Hui Li; Jinfang Tan; Hongwei Xue; Wenming Zheng
• Keywords: 0106 biological sciences; 2. Zero hunger; S; Agriculture (General); Phosphate starvation response; Wheat; Arabidopsis; Agriculture; MADS-box transcription factor; 01 natural sciences; S1-972

Soil inorganic phosphate (Pi) levels are frequently suboptimal for the growth and development of crop plants. Although MADS-box genes participate in diverse plant developmental processes, their involvement in phosphate starvation responses (PSRs) remains unclear. We identified a type I MADS-box transcription factor gene, TaMADS2-3D, which was rapidly induced under low-Pi stress in roots of wheat (Triticum aestivum). A TaMADS2-3D-GFP fusion protein was found located in the nucleus. Transgenic Arabidopsis plants overexpressing TaMADS2-3D (TaMADS2-3DOE) showed shortened primary roots, increased lateral root density, and retarded seedling growth under high-Pi (HP) conditions, accompanied by increased Pi contents in their shoots and roots. The Arabidopsis TaMADS2-3DOE plants showed similar PSR phenotypes under low Pi (LP) conditions. These results indicate constitutive activation of PSRs by overexpression of TaMADS2-3D in Arabidopsis. Reactive oxygen species (ROS), H2O2 and O2−, levels were increased in root tips of Arabidopsis TaMADS2-3DOE plants under HP conditions. Transcriptome analysis of Arabidopsis TaMADS2-3DOE plants under different Pi regimes revealed expression changes for a variety of PSR genes including AtZAT6. Overexpression of TaMADS2-3D in wheat also led to constitutive activation of PSRs. We propose that TaMADS2-3D regulates plant PSRs probably by modulating ROS homeostasis, root development, PSR gene expression, and Pi uptake. This study increases our understanding of plant PSR regulation and provides a valuable gene for improving phosphorus-use efficiency in wheat and other crops.