A stress-responsive bZIP transcription factor OsbZIP62 improves drought and oxidative resistance in rice

Transcription factors play a crucial regulatory role in plant drought stress responses. In this study, a novel drought stress related bZIP transcription factor, OsbZIP62, was identified in rice. This gene was selected from transcriptome analysis of several typical rice varieties with different drought tolerance. The expression of OsbZIP62 was obviously induced by drought, hydrogen peroxide, and abscisic acid (ABA) treatment. Overexpression of OsbZIP62-VP64 (OsbZIP62V) enhanced the drought tolerance and oxidative stress tolerance of transgenic rice, while the osbzip62 mutants showed the opposite phenotype. RNA-seq analysis showed that many stress-related genes (e.g. OsGL1, OsNAC10, and DSM2) were up-regulated in OsbZIP62V plants. OsbZIP62 could bind to the abscisic acid–responsive element (ABRE) and promoters of several putative target genes. Taken together, OsbZIP62 positively regulated rice drought tolerance through regulated the expression of genes associated with stress. Overall design: To search the downstream genes of OsbZIP62, we performed transcriptome analysis of the OsbZIP62-VP64-overexpressor, osbzip62 mutant and wild-type plants under normal conditions using high-throughput sequencing.