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WRKY genes encode transcription factors that are involved in the regulation of various biological processes.OsWRKY51 encodes a group II WRKY protein that contains one WRKY domain with a C2H2-type zinc finger motif. Recently, we identified two ABA-inducible and gibberellin (GA)-repressible rice WRKY genes, namely OsWRKY51 and -71. Although OsWRKY51 itself does not bind to the Amy32b promoter in vitro, it interacts with OsWRKY71 and enhances the binding affinity of OsWRKY71 to W boxes in the Amy32b promoter. Titration experiments suggest that the ratio of repressors (such as OsWRKY51 and OsWRKY71) to the activator (e.g. OsGAMYB) seems to determine the expression level of the Amy32b promoter. These data demonstrate the synergistic interaction of ABA-inducible WRKY genes in regulating GAMYB-mediated GA signaling in aleurone cells, thereby establishing a novel mechanism for ABA and GA signaling cross talk (Zhang et al. 2004; Xie et al. 2006).A model is proposed for the role of OsWRKY51 and OsWRKY71 in mediating the cross-talk of GA and ABA signaling. The OsWRKY51/OsWRKY71 repressors form a heterotetramer to bind the W-boxes, thus exerting an antagonistic effect against GA induction of Amy32b. In contrast, GA induces GAMYB, but suppresses OsWRKY51 and OsWRKY71. The ratio of OsWRKY51/OsWRKY71 to GAMYB is low, so that GAMYB competes against the inhibitory effect of OsWRKY51 and OsWRKY71, leading to a high level of α-amylase gene expression. Obviously, this is an over-simplified model because it does not consider other activators, such as OsDOF3, RAMY, and OsMYBS1/OsMYBS2, as well as other repressors, such as KGM and HRT.Nevertheless, this model gives us new insights about how multiple transcription factors coordinate to fine tune Amy32b expression triggered by different signals.