grek1/2 showed the precocious leaf senescence under normal growth condition.
Plants integrate internal and external signals to determine the timing of leaf senescence initiation, strict regulation of which is essential for maximizing growth and productivity, yet the mechanisms defining the temporal window of senescence remain elusive. Here, we show that a poorly characterized receptor-like kinase family, GREEN KEEPER (GREK), regulates senescence initiation. Several experiments, including phenotypic and transcriptomic analyses, revealed that the dynamics of age-dependent senescence in grek1/2 mutants mirror those of wild-type plants but initiates earlier. This study highlights the GREK family as representing a previously unrecognized receptor pathway regulating senescence timing.