Overexpression of Rice Premnaspirodiene Oxygenase Reduces Infection Rate of Xanthomonas oryzae pv. oryzae

Plants utilize cytochrome P450, a large superfamily of heme-containing mono-oxygenases, in the synthesis of lignins, UV protectants, pigments, defense compounds, fatty acids, hormones, and signaling molecules. Despite the overwhelming rice P450s accessions assorted in the database, functional studies are lacking. So far, there is no evidence involving rice P450s in disease immunity. Most of our understanding has been based on other plant systems that are mostly dicot. In this study, we isolated the cytochrome P450 (OsCYP71) in rice and screened the gene using gain-of-function technique. The full-length cDNA of OsCYP71 was constitutively overexpressed using 35S promoter. Here, we explored the functions of OsCYP71 in rice - Xanthomonas oryzae pv. oryzae pathosystem, and initially demonstrated using gene expression assays the interesting correlation of PR genes activations and magnitude of resistance in P450-mediated immunity.