Rice Science (Mar 2024)
OsbZIP53 Negatively Regulates Immunity Response by Involving in Reactive Oxygen Species and Salicylic Acid Metabolism in Rice
Abstract
The basic region/leucine zipper (bZIP) transcription factors play important roles in plant development and responses to abiotic and biotic stresses. OsbZIP53 regulates resistance to Magnaporthe oryzae in rice by analyzing APIP5-RNAi transgenic plants. To further investigate the biological functions of OsbZIP53, we generated osbzip53 mutants using CRISPR/Cas9 editing and also constructed OsbZIP53 over-expression transgenic plants. Comprehensive analysis of phenotypical, physiological, and transcriptional data showed that knocking-out OsbZIP53 not only improved disease resistance by inducing a hypersensitivity response in plants, but also regulated the immune response through the salicylic acid pathway. Specifically, disrupting OsbZIP53 increased H2O2 accumulation by promoting reactive oxygen species generation through up-regulation of several respiratory burst oxidase homologs (Osrboh genes) and weakened H2O2 degradation by directly targeting OsMYBS1. In addition, the growth of osbzip53 mutants was seriously impaired, while OsbZIP53 over-expression lines displayed a similar phenotype to the wild type, suggesting that OsbZIP53 has a balancing effect on rice immune response and growth.