Abstract
In plants, ABA levels increase in response to drought stress, and then such ABA is thought to regulate the expression of many genes that function in the stress tolerance. In the promoters of such ABA-regulated genes, the conserved cis-elements designated ABREs (ABA-responsive elements), which control expression of ABA-responsive genes, have been identified. The Arabidopsis cDNAs encoding bZIP-type transcription factors referred as ABRE-binding (AREB) proteins, were isolated using the yeast one-hybrid screening. We demonstrated that AREB1, one of the AREBs, is a transcriptional activator of novel ABRE-dependent ABA signaling involved in enhancing drought stress tolerance. In this study, we have identified OsAREB genes, rice AREB orthologs, by using the public rice genome databases and large-scale transcriptome analyses. Based on the molecular characterization of OsAREB genes, we will discuss the roles of the OsAREB genes in water stress response.
