Figure 2.

E3 ligases involved in ABA signaling. The schematic of known UPS components in ABA signaling illustrates that there is regulation of a single substrate (ABI5) by multiple E3 ligases and a number of different classes of E3s act at multiple levels in the ABA pathway, including biosynthesis and downstream gene regulation. RING-type E3 ligases are shown as yellow pentagons, U-box-type E3 ligases as dark orange pentagons, CRL E3 ligases as orange pentagons, and CRL3-based E3 ligases as pink pentagons. AFP is depicted is a green square, and COP1 is a gray triangle. Known (or unknown) ligase substrates are blue pie wedges.