Figure 6.
The activation of the ZAR1 immune receptor. ZAR1 (orange) is an Arabidopsis CC-NLR that forms complexes with pseudokinases, including ZED1 and RKS1 (green), to perceive effector activity (208). The ZAR1:RKS1 receptor complex guards the receptor-like cytoplasmic decoy kinase PBL2. Following uridylylation of PBL2 by the Xanthomonas campestris effector protein AvrAC, PBL2UMP (purple) binds to RKS1, activating ZAR1. Activated ZAR1 is then able to oligomerize into a pentameric wheel with the CC domains each contributing their H1 helix (yellow) to form a funnel-like structure.