Figure 2.

Kinase-mediated post-translational modification of core components of the ABA signaling pathway. CARK1, CEPR2, TOR kinase, and AEL phosphorylate PYLs. CARK1 positively regulates ABA signaling by enhancing PYLs activity on the cytoplasm. In contrast, CEPR2 and AEL negatively regulate ABA signaling by promoting degradation of PYLs. TOR kinase also plays negative role in ABA signaling by preventing PYL activation. CEPR2 acts on PM. ABI1 and ABI2 are phosphorylated and enhanced in their phosphatase activity by PR5K2 on the PM. BIN2 and RAF10 phosphorylate SnRK2s enhancing their kinase activity on the cytoplasm and nucleus.