Figure 1.

A model for G protein activation by pattern-recognition receptors (PRRs). In the resting state, regulator of G protein signalling 1 (RGS1) associates with PRR complexes to maintain the Gα protein in the inactive state. Upon perception of patterns, RLCKs are activated, which in turn phosphorylate RGS1. Phosphorylation on RGS1 leads to its dissociation from the Gα proteins, and the G proteins are auto-activated in the absence of RGS1-mediated inhibition. The activated G proteins then positively regulate downstream immune signalling. SERKs, SOMATIC EMBRYOGENESIS RECEPTOR KINASES; p, phosphorylation.