摘要
Drought stress severely limits rice productivity.Understanding of drought-response mechanisms in rice is essential for developing climate-resilient varieties.While cysteine-rich receptor-like kinases(CRKs)are primarily implicated in plant development and immunity,their role in drought response remains poorly understood.In this study,we identified a CRK,OsCRK14,as a key positive regulator of drought resistance in rice.We demonstrated that plasma membrane-localized OsCRK14 phosphorylates the receptor-like cytoplasmic kinase OsRLCK57 under drought stress,leading to activate a mitogen-activated protein kinase(MAPK)cascade(OsMKKK10-OsMKK4-OsMPK6).Activated OsMPK6 directly phosphorylates the abscisic acid-responsive transcription factor OsbZIP66 at conserved Serine-Proline/Threonine-Proline motifs,enhancing its stability and promoting drought-responsive gene expression.Furthermore,we found that natural variations in the OsCRK14 promoter influence its transcript levels due to the altered OsMYB72 binding affinities,which are correlated with drought-resistance differences among rice varieties.Collectively,our study discovers a novel CRK-RLCK-MAPK-bZIP signaling pathway that connects membrane signal sensing to transcriptional regulation in drought response,providing both mechanistic insights and genetic resources for breeding drought-resistant rice.
基金
supported by the Biological Breeding-National Science and Technology Major Project(2023ZD0407105)
the National Natural Science Foundation of China(32272041,U21A20207)
the National Key Research and Development Program of China(2023YFF1002400)
the Innovative Project of Hubei Hongshan Laboratory(2022hszd015)
the Natural Science Foundation of Hubei Province(2024AFB714,2023AFA095,2022CFA024)
the Earmarked Fund for China Agriculture Research System(CARS-01)
the Fundamental Research Funds for the Central Universities(2662025SKPY007).
