Abstract
Rice blast caused by Magnaporthe oryzae poses a major threat to world food supply. Conditions conducive to the disease include insufficient light. Our previous studies found that light-dependent phosphorylation of light-harvesting complex II protein (LHCB5) mediates rice immunity; however, the underlying mechanisms, in particular, the upstream regulators of LHCB5 phosphorylation, remain unknown. Here, we show that OsLIKE1 functions as a lectin receptor-like kinase (LecRLK) to play a critical role in rice resistance against M. oryzae. OsLIKE1 interacts with and phosphorylates LHCB5. In addition, we find two phosphorylation sites in the kinase domain of OsLIKE1 important for its auto-phosphorylation and phosphorylation of LHCB5. Moreover, we find that variation in light-induced OsLIKE1 expression is driven by specific single-nucleotide polymorphisms (SNPs) within the promoter region. These SNPs promote the auto-phosphorylation of OsLIKE1 to phosphorylate LHCB5 and activate its immune function against the blast fungus. Collectively, these findings elucidate the mechanism by which light regulates OsLIKE1-dependent defense in rice and support SNP-based rice breeding programs that increase disease resistance.