A Rice bZIP Transcription Factor Regulates Duf630/632 Domain Protein in Response to Drought Stress

Drought severely affects crop yields and poses a great threat to food security. It is an urgent task to mine drought tolerance genes and breed new varieties. In previous studies, transcription factors such as Basic Leucine Zipper (bZIP), Dehydration-Responsive Element Binding (DREB), DNABinding with One Finger (DOF), Heat Shock Transcription Factor (HSF), v-Myb Myeloblastosis Viral Oncogene Homolog (MYB) etc., have been found to be key factors in response to drought stress, and the corresponding regulatory mechanisms have been gradually analyzed. Among them, the bZIP family has been shown to respond to drought stress through multiple pathways in plants. Recently, our team screened OsBBP1, the downstream target of drought tolerance regulator OsbZIP72, through Chip-seq technology. OsBBP1, a typical DUF630/632 domain protein, is localized in the nucleus and cytoplasm, and the DUF632 domain contributes to its localization in the cytoplasm. Through gene function identification, it is discovered that OsBBP1 was induced by Polyethylene Glycol (PEG) and Abscisic Acid (ABA) and positively regulated rice drought tolerance. Further, OsBBP1 affects Reactive Oxygen Species (ROS) accumulation in plants by regulating ROS scavenging enzyme activity under drought conditions were found, thereby improving the survival rate of rice. The study revealed that the bZIP transcription factor family responds to drought stress by regulating DUF domain protein, and provided another regulatory pathway for plant resistance to abiotic stress.