Osmotic stress activated protein kinase 5 (SAPK5) positively regulates immune response and blast resistance in rice

Abstract

Background The sucrose non-fermenting 1 (SNF1) related protein kinase 2 (SnRK2) family proteins are plant-specific Ser/Thr protein kinases that are mainly involved in response to abiotic stress. However, their regulation roles on immune response and disease resistance in crops are largely unknown. Results In this study, we report the characterization of a rice SnRK2 family member, osmotic stress activated protein kinases 5 (SAPK5), on plant immune response. The SAPK5 protein is localized in cytoplasm and possesses kinase activity. The kinase activity of SAPK5 is promoted upon treatment with chitin, a conserved pathogen-associated molecular pattern (PAMP). Knockout of SAPK5 compromises rice immune response and resistance against the fungal pathogen Magnaporthe oryzae. Conclusions Our study demonstrates that SAPK5 positively regulates immune response and disease resistance in rice and provides new insights into the regulatory roles of SnRK2 proteins on plant immunity.