Characterization of Transcription Factor Gene OsDRAP1 Conferring Drought Tolerance in Rice

Abstract

<b>HIGHLIGHTS</b> Overexpressing and RNA interfering <i>OsDRAP1</i> transgenic rice plants exhibited significantly improved and reduced drought tolerance, but accompanied with negative effects on development and yield. The dehydration responsive element binding (DREBs) genes are important transcription factors which play a crucial role in plant abiotic stress tolerances. In this study, we functionally characterized a DREB2-like gene, <i>OsDRAP1</i> conferring drought tolerance (DT) in rice. <i>OsDRAP1</i>, containing many <i>cis</i>-elements in its promoter region, was expressed in all organs (mainly expressed in vascular tissues) of rice, and induced by a variety of environmental stresses and plant hormones. Overexpressing <i>OsDRAP1</i> transgenic plants exhibited significantly improved DT; while <i>OsDRAP1</i> RNA interfering plants exhibited significantly reduced DT which also accompanied with significant negative effects on development and yield. Overexpression of <i>OsDRAP1</i> has a positive impact on maintaining water balance, redox homeostasis and vascular development in transgenic rice plants under drought stress. <i>OsDRAP1</i> interacted with many genes/proteins and could activate many downstream DT related genes, including important transcription factors such as <i>OsCBSX3</i> to response drought stress, indicating the <i>OsDRAP1</i>-mediated pathways for DT involve complex genes networks. All these results provide a basis for further complete understanding of the <i>OsDRAP1</i> mediated gene networks and their related phenotypic effects.