OsCAMTA3 Negatively Regulates Disease Resistance to by Associating with OsCAMTAPL in Rice.

Rice () is one of the most important staple foods worldwide. However, rice blast disease, caused by the ascomycete fungus , seriously affects the yield and quality of rice. Calmodulin-binding transcriptional activators (CAMTAs) play vital roles in the response to biotic stresses. In this study, we showed that OsCAMTA3 and CAMTA PROTEIN LIKE (OsCAMTAPL), an OsCAMTA3 homolog that lacks the DNA-binding domain, functioned together in negatively regulating disease resistance in rice. OsCAMTA3 associated with OsCAMTAPL. The and mutants showed enhanced resistance compared to wild-type plants, and double mutants showed more robust resistance to than or . An RNA-Seq analysis revealed that 59 and 73 genes, respectively, were differentially expressed in wild-type plants and before and after inoculation with , including , an acetaldehyde dehydrogenase that negatively regulates plant immunity. OsCAMTA3 could directly bind to the promoter of , and expression was decreased in , , and mutants. In conclusion, OsCAMTA3 associates with OsCAMTAPL to regulate disease resistance by binding and activating the expression of in rice, which reveals a strategy by which rice controls rice blast disease and provides important genes for resistance breeding holding a certain positive impact on ensuring food security.