As the last stage of leaf development,senescence is a fine-tuned process regulated by interplays of multiple signaling pathways.We have previously identified GmSARK,a LRR-RLK from soybean,as a positive regulator of leaf senescence.Here we report the elucidation of the molecular mechanism of GmSARK-mediated leaf senescence,especially its specific roles in senescence-inducing hormonal pathways.A glucocorticoid-inducible transcription system was used to produce transgenic Arabidopsis plants for inducible over-expression of GmSARK,which led to early leaf senescence,chloroplast destruction and abnormal flower morphology in Arabidopsis.