Figure 10

Proposed model for involvement of WRKY18, WRKY40 and WRKY60 in ABA responses. ABA induction of WRKY18 and WRKY40 leads to increase in WRKY18 and WRKY40 proteins that form both homo- and heterocomplexes through physical interactions. The requirement of both WRKY18 and WRKY40 for induction of WRKY60 suggest possible involvement of a WRKY18/WRKY40 heterocomplex that may recognize the W box sequences in the WRKY60 gene promoter and activate its expression. WRKY18 and WRKY60 positively regulate while WRKY40 negatively regulates plant responses to ABA probably by modulating ABA-regulated genes.