Identification of Ossnrk1a-1 Regulated Genes Associated with Rice Immunity and Seed Set.

Sucrose non-fermenting-1-related protein kinase-1 (SnRK1) is a highly conserved serine-threonine kinase complex regulating plants' energy metabolisms and resistance to various types of stresses. However, the downstream genes regulated by SnRK1 in these plant physiological processes still need to be explored. In this study, we found that the knockout of resulted in no obvious defects in rice growth but notably decreased the seed setting rate. The mutants were more sensitive to blast fungus () infection and showed compromised immune responses. Transcriptome analyses revealed that SnRK1a was an important intermediate in the energy metabolism and response to biotic stress. Further investigation confirmed that the transcription levels of , which positively controls rice yield, and the defense-related gene () were remarkably decreased in the mutant. Moreover, we found that OsSnRK1a directly interacted with the regulatory subunits OsSnRK1β1 and OsSnRK1β3, which responded specifically to blast fungus infection and starvation stresses, respectively. Taken together, our findings provide an insight into the mechanism of OsSnRK1a, which forms a complex with specific β subunits, contributing to rice seed set and resistance by regulating the transcription of related genes.