Overexpression of the lectin receptor-like kinase gene OsLecRK-S.7 inhibits plant growth and enhances disease resistance in rice

Lectin receptor-like kinases (LecRKs) are a critical class of plant proteins that play essential roles in plant development as well as in responses to both biotic and abiotic stresses. In this study, we found that overexpression of the L-type Lectin receptor kinase gene OsLecRK-S.7 severely inhibits plant growth and triggers spontaneous cell death. Meanwhile, immune responses, including pathogenesis-related (PR) gene expression and reactive oxygen species (ROS) accumulation, were elevated in OsLecRK-S.7 overexpressing plants. Kinase inactivation experiments demonstrated that kinase activity was essential for OsLecRK-S.7-mediated constitutive immunity. Infection assays further demonstrated that overexpression of OsLecRK-S.7 enhances rice resistance to bacterial blight. Additionally, bimolecular fluorescence complementation (BiFC) and pull-down experiments identified interactions between OsLecRK-S.7 and receptor-like cytoplasmic kinases (RLCKs) OsRLCK118, OsRLCK185, and OsRLCK107 that are involved in immune signaling. These findings suggest that OsLecRK-S.7 is a significant regulator of plant immunity, likely promoting cell death and immune responses through its interactions with OsRLCK118, OsRLCK185, and OsRLCK107.