Figure 9.

The Working Model of WRKY57 Functions in JA-Induced Leaf Senescence.

Auxin and JA antagonistically regulate leaf senescence through WRKY57. JAZ4/8 and IAA29 function as negative and positive regulators, respectively, in JA-induced leaf senescence, and they competitively interact with the zinc-finger domain of WRKY57. At the protein level, WRKY57 is induced by auxin but repressed by JA. WRKY57 directly binds to the promoters of SEN4 and SAG12 and then represses their transcription. The solid lines indicate direct interaction or regulation. The dashed lines indicate indirect regulation.